1 | #! perl |
1 | #! perl |
2 | |
2 | |
3 | our $EXPR = 'move load "/root/pix/das_fette_schwein.jpg", &x, &y'; |
3 | #:META:X_RESOURCE:%.expr:string:background expression |
4 | #$EXPR = 'blur root, 10, 10' |
4 | #:META:X_RESOURCE:%.border:boolean:respect the terminal border |
5 | #$EXPR = 'blur move (root, -x, -y), 5, 5' |
5 | #:META:X_RESOURCE:%.interval:seconds:minimum time between updates |
6 | #resize load "/root/pix/das_fette_schwein.jpg", w, h |
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7 | |
6 | |
8 | use Safe; |
7 | =head1 NAME |
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8 | |
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9 | background - manage terminal background |
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10 | |
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11 | =head1 SYNOPSIS |
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12 | |
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13 | urxvt --background-expr 'background expression' |
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14 | --background-border |
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15 | --background-interval seconds |
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16 | |
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17 | =head1 DESCRIPTION |
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18 | |
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19 | This extension manages the terminal background by creating a picture that |
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20 | is behind the text, replacing the normal background colour. |
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21 | |
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22 | It does so by evaluating a Perl expression that I<calculates> the image on |
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23 | the fly, for example, by grabbing the root background or loading a file. |
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24 | |
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25 | While the full power of Perl is available, the operators have been design |
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26 | to be as simple as possible. |
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27 | |
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28 | For example, to load an image and scale it to the window size, you would |
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29 | use: |
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30 | |
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31 | urxvt --background-expr 'scale keep { load "/path/to/mybg.png" }' |
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32 | |
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33 | Or specified as a X resource: |
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34 | |
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35 | URxvt.background-expr: scale keep { load "/path/to/mybg.png" } |
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36 | |
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37 | =head1 THEORY OF OPERATION |
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38 | |
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39 | At startup, just before the window is mapped for the first time, the |
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40 | expression is evaluated and must yield an image. The image is then |
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41 | extended as necessary to cover the whole terminal window, and is set as a |
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42 | background pixmap. |
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43 | |
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44 | If the image contains an alpha channel, then it will be used as-is in |
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45 | visuals that support alpha channels (for example, for a compositing |
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46 | manager). In other visuals, the terminal background colour will be used to |
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47 | replace any transparency. |
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48 | |
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49 | When the expression relies, directly or indirectly, on the window size, |
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50 | position, the root pixmap, or a timer, then it will be remembered. If not, |
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51 | then it will be removed. |
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52 | |
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53 | If any of the parameters that the expression relies on changes (when the |
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54 | window is moved or resized, its position or size changes; when the root |
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55 | pixmap is replaced by another one the root background changes; or when the |
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56 | timer elapses), then the expression will be evaluated again. |
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57 | |
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58 | For example, an expression such as C<scale keep { load "$HOME/mybg.png" |
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59 | }> scales the image to the window size, so it relies on the window size |
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60 | and will be reevaluated each time it is changed, but not when it moves for |
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61 | example. That ensures that the picture always fills the terminal, even |
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62 | after its size changes. |
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63 | |
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64 | =head2 EXPRESSIONS |
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65 | |
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66 | Expressions are normal Perl expressions, in fact, they are Perl blocks - |
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67 | which means you could use multiple lines and statements: |
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68 | |
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69 | scale keep { |
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70 | again 3600; |
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71 | if (localtime now)[6]) { |
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72 | return load "$HOME/weekday.png"; |
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73 | } else { |
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74 | return load "$HOME/sunday.png"; |
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75 | } |
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76 | } |
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77 | |
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78 | This inner expression is evaluated once per hour (and whenever the |
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79 | terminal window is resized). It sets F<sunday.png> as background on |
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80 | Sundays, and F<weekday.png> on all other days. |
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81 | |
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82 | Fortunately, we expect that most expressions will be much simpler, with |
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83 | little Perl knowledge needed. |
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84 | |
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85 | Basically, you always start with a function that "generates" an image |
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86 | object, such as C<load>, which loads an image from disk, or C<root>, which |
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87 | returns the root window background image: |
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88 | |
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89 | load "$HOME/mypic.png" |
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90 | |
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91 | The path is usually specified as a quoted string (the exact rules can be |
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92 | found in the L<perlop> manpage). The F<$HOME> at the beginning of the |
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93 | string is expanded to the home directory. |
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94 | |
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95 | Then you prepend one or more modifiers or filtering expressions, such as |
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96 | C<scale>: |
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97 | |
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98 | scale load "$HOME/mypic.png" |
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99 | |
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100 | Just like a mathematical expression with functions, you should read these |
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101 | expressions from right to left, as the C<load> is evaluated first, and |
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102 | its result becomes the argument to the C<scale> function. |
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103 | |
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104 | Many operators also allow some parameters preceding the input image |
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105 | that modify its behaviour. For example, C<scale> without any additional |
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106 | arguments scales the image to size of the terminal window. If you specify |
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107 | an additional argument, it uses it as a scale factor (multiply by 100 to |
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108 | get a percentage): |
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109 | |
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110 | scale 2, load "$HOME/mypic.png" |
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111 | |
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112 | This enlarges the image by a factor of 2 (200%). As you can see, C<scale> |
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113 | has now two arguments, the C<200> and the C<load> expression, while |
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114 | C<load> only has one argument. Arguments are separated from each other by |
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115 | commas. |
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116 | |
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117 | Scale also accepts two arguments, which are then separate factors for both |
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118 | horizontal and vertical dimensions. For example, this halves the image |
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119 | width and doubles the image height: |
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120 | |
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121 | scale 0.5, 2, load "$HOME/mypic.png" |
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122 | |
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123 | IF you try out these expressions, you might suffer from some sluggishness, |
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124 | because each time the terminal is resized, it loads the PNG image again |
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125 | and scales it. Scaling is usually fast (and unavoidable), but loading the |
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126 | image can be quite time consuming. This is where C<keep> comes in handy: |
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127 | |
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128 | scale 0.5, 2, keep { load "$HOME/mypic.png" } |
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129 | |
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130 | The C<keep> operator executes all the statements inside the braces only |
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131 | once, or when it thinks the outcome might change. In other cases it |
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132 | returns the last value computed by the brace block. |
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133 | |
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134 | This means that the C<load> is only executed once, which makes it much |
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135 | faster, but also means that more memory is being used, because the loaded |
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136 | image must be kept in memory at all times. In this expression, the |
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137 | trade-off is likely worth it. |
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138 | |
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139 | But back to effects: Other effects than scaling are also readily |
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140 | available, for example, you can tile the image to fill the whole window, |
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141 | instead of resizing it: |
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142 | |
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143 | tile keep { load "$HOME/mypic.png" } |
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144 | |
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145 | In fact, images returned by C<load> are in C<tile> mode by default, so the |
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146 | C<tile> operator is kind of superfluous. |
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147 | |
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148 | Another common effect is to mirror the image, so that the same edges |
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149 | touch: |
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150 | |
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151 | mirror keep { load "$HOME/mypic.png" } |
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152 | |
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153 | Another common background expression is: |
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154 | |
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155 | rootalign root |
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156 | |
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157 | This one first takes a snapshot of the screen background image, and then |
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158 | moves it to the upper left corner of the screen (as opposed to the upper |
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159 | left corner of the terminal window)- the result is pseudo-transparency: |
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160 | the image seems to be static while the window is moved around. |
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161 | |
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162 | =head2 COLOUR SPECIFICATIONS |
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163 | |
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164 | Whenever an operator expects a "colour", then this can be specified in one |
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165 | of two ways: Either as string with an X11 colour specification, such as: |
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166 | |
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167 | "red" # named colour |
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168 | "#f00" # simple rgb |
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169 | "[50]red" # red with 50% alpha |
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170 | "TekHVC:300/50/50" # anything goes |
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171 | |
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172 | OR as an array reference with one, three or four components: |
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173 | |
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174 | [0.5] # 50% gray, 100% alpha |
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175 | [0.5, 0, 0] # dark red, no green or blur, 100% alpha |
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176 | [0.5, 0, 0, 0.7] # same with explicit 70% alpha |
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177 | |
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178 | =head2 CACHING AND SENSITIVITY |
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179 | |
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180 | Since some operations (such as C<load> and C<blur>) can take a long time, |
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181 | caching results can be very important for a smooth operation. Caching can |
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182 | also be useful to reduce memory usage, though, for example, when an image |
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183 | is cached by C<load>, it could be shared by multiple terminal windows |
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184 | running inside urxvtd. |
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185 | |
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186 | =head3 C<keep { ... }> caching |
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187 | |
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188 | The most important way to cache expensive operations is to use C<keep { |
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189 | ... }>. The C<keep> operator takes a block of multiple statements enclosed |
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190 | by C<{}> and keeps the return value in memory. |
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191 | |
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192 | An expression can be "sensitive" to various external events, such as |
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193 | scaling or moving the window, root background changes and timers. Simply |
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194 | using an expression (such as C<scale> without parameters) that depends on |
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195 | certain changing values (called "variables"), or using those variables |
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196 | directly, will make an expression sensitive to these events - for example, |
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197 | using C<scale> or C<TW> will make the expression sensitive to the terminal |
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198 | size, and thus to resizing events. |
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199 | |
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200 | When such an event happens, C<keep> will automatically trigger a |
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201 | reevaluation of the whole expression with the new value of the expression. |
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202 | |
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203 | C<keep> is most useful for expensive operations, such as C<blur>: |
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204 | |
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205 | rootalign keep { blur 20, root } |
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206 | |
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207 | This makes a blurred copy of the root background once, and on subsequent |
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208 | calls, just root-aligns it. Since C<blur> is usually quite slow and |
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209 | C<rootalign> is quite fast, this trades extra memory (for the cached |
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210 | blurred pixmap) with speed (blur only needs to be redone when root |
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211 | changes). |
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212 | |
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213 | =head3 C<load> caching |
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214 | |
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215 | The C<load> operator itself does not keep images in memory, but as long as |
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216 | the image is still in memory, C<load> will use the in-memory image instead |
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217 | of loading it freshly from disk. |
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218 | |
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219 | That means that this expression: |
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220 | |
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221 | keep { load "$HOME/path..." } |
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222 | |
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223 | Not only caches the image in memory, other terminal instances that try to |
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224 | C<load> it can reuse that in-memory copy. |
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225 | |
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226 | =head1 REFERENCE |
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227 | |
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228 | =head2 COMMAND LINE SWITCHES |
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229 | |
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230 | =over 4 |
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231 | |
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232 | =item --background-expr perl-expression |
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233 | |
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234 | Specifies the Perl expression to evaluate. |
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235 | |
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236 | =item --background-border |
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237 | |
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238 | By default, the expression creates an image that fills the full window, |
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239 | overwriting borders and any other areas, such as the scrollbar. |
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240 | |
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241 | Specifying this flag changes the behaviour, so that the image only |
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242 | replaces the background of the character area. |
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243 | |
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244 | =item --background-interval seconds |
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245 | |
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246 | Since some operations in the underlying XRender extension can effectively |
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247 | freeze your X-server for prolonged time, this extension enforces a minimum |
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248 | time between updates, which is normally about 0.1 seconds. |
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249 | |
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250 | If you want to do updates more often, you can decrease this safety |
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251 | interval with this switch. |
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252 | |
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253 | =back |
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254 | |
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255 | =cut |
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256 | |
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257 | our %_IMG_CACHE; |
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258 | our $HOME; |
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259 | our ($self, $frame); |
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260 | our ($x, $y, $w, $h); |
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261 | |
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262 | # enforce at least this interval between updates |
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263 | our $MIN_INTERVAL = 6/59.951; |
9 | |
264 | |
10 | { |
265 | { |
11 | package urxvt::bgdsl::vars; |
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12 | |
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13 | our ($self, $old, $new); |
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14 | our ($x, $y, $w, $h); |
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15 | |
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16 | package urxvt::bgdsl; # background language |
266 | package urxvt::bgdsl; # background language |
17 | |
267 | |
18 | *repeat_black = \&urxvt::RepeatNone; #TODO wtf |
268 | sub FR_PARENT() { 0 } # parent frame, if any - must be #0 |
19 | *repeat_wrap = \&urxvt::RepeatNormal; |
269 | sub FR_CACHE () { 1 } # cached values |
20 | *repeat_pad = \&urxvt::RepeatPad; |
270 | sub FR_AGAIN () { 2 } # what this expr is sensitive to |
21 | *repeat_mirror = \&urxvt::RepeatReflect; |
271 | sub FR_STATE () { 3 } # watchers etc. |
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272 | |
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273 | use List::Util qw(min max sum shuffle); |
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274 | |
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275 | =head2 PROVIDERS/GENERATORS |
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276 | |
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277 | These functions provide an image, by loading it from disk, grabbing it |
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278 | from the root screen or by simply generating it. They are used as starting |
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279 | points to get an image you can play with. |
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280 | |
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281 | =over 4 |
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282 | |
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283 | =item load $path |
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284 | |
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285 | Loads the image at the given C<$path>. The image is set to plane tiling |
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286 | mode. |
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287 | |
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288 | If the image is already in memory (e.g. because another terminal instance |
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289 | uses it), then the in-memory copy us returned instead. |
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290 | |
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291 | =item load_uc $path |
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292 | |
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293 | Load uncached - same as load, but does not cache the image, which means it |
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294 | is I<always> loaded from the filesystem again, even if another copy of it |
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295 | is in memory at the time. |
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296 | |
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297 | =cut |
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298 | |
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299 | sub load_uc($) { |
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300 | $self->new_img_from_file ($_[0]) |
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301 | } |
22 | |
302 | |
23 | sub load($) { |
303 | sub load($) { |
24 | my ($path) = @_; |
304 | my ($path) = @_; |
25 | |
305 | |
26 | $new->{load}{$path} = $old->{load}{$path} || $self->new_img_from_file ($path); |
306 | $_IMG_CACHE{$path} || do { |
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307 | my $img = load_uc $path; |
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308 | Scalar::Util::weaken ($_IMG_CACHE{$path} = $img); |
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309 | $img |
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310 | } |
27 | } |
311 | } |
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312 | |
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313 | =item root |
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314 | |
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315 | Returns the root window pixmap, that is, hopefully, the background image |
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316 | of your screen. |
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317 | |
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318 | This function makes your expression root sensitive, that means it will be |
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319 | reevaluated when the bg image changes. |
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320 | |
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321 | =cut |
28 | |
322 | |
29 | sub root() { |
323 | sub root() { |
30 | die "root op not supported, exg, we need you"; |
324 | $frame->[FR_AGAIN]{rootpmap} = 1; |
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325 | $self->new_img_from_root |
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326 | } |
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327 | |
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328 | =item solid $colour |
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329 | |
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330 | =item solid $width, $height, $colour |
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331 | |
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332 | Creates a new image and completely fills it with the given colour. The |
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333 | image is set to tiling mode. |
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334 | |
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335 | If C<$width> and C<$height> are omitted, it creates a 1x1 image, which is |
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336 | useful for solid backgrounds or for use in filtering effects. |
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337 | |
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338 | =cut |
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339 | |
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340 | sub solid($;$$) { |
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341 | my $colour = pop; |
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342 | |
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343 | my $img = $self->new_img (urxvt::PictStandardARGB32, 0, 0, $_[0] || 1, $_[1] || 1); |
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344 | $img->fill ($colour); |
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345 | $img |
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346 | } |
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347 | |
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348 | =item clone $img |
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349 | |
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350 | Returns an exact copy of the image. This is useful if you want to have |
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351 | multiple copies of the same image to apply different effects to. |
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352 | |
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353 | =cut |
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354 | |
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355 | sub clone($) { |
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356 | $_[0]->clone |
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357 | } |
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358 | |
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359 | =item merge $img ... |
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360 | |
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361 | Takes any number of images and merges them together, creating a single |
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362 | image containing them all. The tiling mode of the first image is used as |
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363 | the tiling mode of the resulting image. |
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364 | |
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365 | This function is called automatically when an expression returns multiple |
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366 | images. |
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367 | |
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368 | =cut |
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369 | |
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370 | sub merge(@) { |
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371 | return $_[0] unless $#_; |
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372 | |
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373 | # rather annoyingly clumsy, but optimisation is for another time |
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374 | |
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375 | my $x0 = +1e9; |
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376 | my $y0 = +1e9; |
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377 | my $x1 = -1e9; |
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378 | my $y1 = -1e9; |
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379 | |
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380 | for (@_) { |
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381 | my ($x, $y, $w, $h) = $_->geometry; |
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382 | |
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383 | $x0 = $x if $x0 > $x; |
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384 | $y0 = $y if $y0 > $y; |
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385 | |
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386 | $x += $w; |
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387 | $y += $h; |
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388 | |
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389 | $x1 = $x if $x1 < $x; |
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390 | $y1 = $y if $y1 < $y; |
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391 | } |
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392 | |
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393 | my $base = $self->new_img (urxvt::PictStandardARGB32, $x0, $y0, $x1 - $x0, $y1 - $y0); |
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394 | $base->repeat_mode ($_[0]->repeat_mode); |
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395 | $base->fill ([0, 0, 0, 0]); |
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396 | |
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397 | $base->draw ($_) |
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398 | for @_; |
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399 | |
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400 | $base |
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401 | } |
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402 | |
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403 | =head2 TILING MODES |
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404 | |
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405 | The following operators modify the tiling mode of an image, that is, the |
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406 | way that pixels outside the image area are painted when the image is used. |
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407 | |
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408 | =over 4 |
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409 | |
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410 | =item tile $img |
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411 | |
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412 | Tiles the whole plane with the image and returns this new image - or in |
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413 | other words, it returns a copy of the image in plane tiling mode. |
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414 | |
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415 | Example: load an image and tile it over the background, without |
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416 | resizing. The C<tile> call is superfluous because C<load> already defaults |
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417 | to tiling mode. |
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418 | |
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419 | tile load "mybg.png" |
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420 | |
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421 | =item mirror $img |
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422 | |
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423 | Similar to tile, but reflects the image each time it uses a new copy, so |
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424 | that top edges always touch top edges, right edges always touch right |
|
|
425 | edges and so on (with normal tiling, left edges always touch right edges |
|
|
426 | and top always touch bottom edges). |
|
|
427 | |
|
|
428 | Example: load an image and mirror it over the background, avoiding sharp |
|
|
429 | edges at the image borders at the expense of mirroring the image itself |
|
|
430 | |
|
|
431 | mirror load "mybg.png" |
|
|
432 | |
|
|
433 | =item pad $img |
|
|
434 | |
|
|
435 | Takes an image and modifies it so that all pixels outside the image area |
|
|
436 | become transparent. This mode is most useful when you want to place an |
|
|
437 | image over another image or the background colour while leaving all |
|
|
438 | background pixels outside the image unchanged. |
|
|
439 | |
|
|
440 | Example: load an image and display it in the upper left corner. The rest |
|
|
441 | of the space is left "empty" (transparent or whatever your compositor does |
|
|
442 | in alpha mode, else background colour). |
|
|
443 | |
|
|
444 | pad load "mybg.png" |
|
|
445 | |
|
|
446 | =item extend $img |
|
|
447 | |
|
|
448 | Extends the image over the whole plane, using the closest pixel in the |
|
|
449 | area outside the image. This mode is mostly useful when you use more complex |
|
|
450 | filtering operations and want the pixels outside the image to have the |
|
|
451 | same values as the pixels near the edge. |
|
|
452 | |
|
|
453 | Example: just for curiosity, how does this pixel extension stuff work? |
|
|
454 | |
|
|
455 | extend move 50, 50, load "mybg.png" |
|
|
456 | |
|
|
457 | =cut |
|
|
458 | |
|
|
459 | sub pad($) { |
|
|
460 | my $img = $_[0]->clone; |
|
|
461 | $img->repeat_mode (urxvt::RepeatNone); |
|
|
462 | $img |
|
|
463 | } |
|
|
464 | |
|
|
465 | sub tile($) { |
|
|
466 | my $img = $_[0]->clone; |
|
|
467 | $img->repeat_mode (urxvt::RepeatNormal); |
|
|
468 | $img |
|
|
469 | } |
|
|
470 | |
|
|
471 | sub mirror($) { |
|
|
472 | my $img = $_[0]->clone; |
|
|
473 | $img->repeat_mode (urxvt::RepeatReflect); |
|
|
474 | $img |
|
|
475 | } |
|
|
476 | |
|
|
477 | sub extend($) { |
|
|
478 | my $img = $_[0]->clone; |
|
|
479 | $img->repeat_mode (urxvt::RepeatPad); |
|
|
480 | $img |
|
|
481 | } |
|
|
482 | |
|
|
483 | =back |
|
|
484 | |
|
|
485 | =head2 VARIABLE VALUES |
|
|
486 | |
|
|
487 | The following functions provide variable data such as the terminal window |
|
|
488 | dimensions. They are not (Perl-) variables, they just return stuff that |
|
|
489 | varies. Most of them make your expression sensitive to some events, for |
|
|
490 | example using C<TW> (terminal width) means your expression is evaluated |
|
|
491 | again when the terminal is resized. |
|
|
492 | |
|
|
493 | =over 4 |
|
|
494 | |
|
|
495 | =item TX |
|
|
496 | |
|
|
497 | =item TY |
|
|
498 | |
|
|
499 | Return the X and Y coordinates of the terminal window (the terminal |
|
|
500 | window is the full window by default, and the character area only when in |
|
|
501 | border-respect mode). |
|
|
502 | |
|
|
503 | Using these functions make your expression sensitive to window moves. |
|
|
504 | |
|
|
505 | These functions are mainly useful to align images to the root window. |
|
|
506 | |
|
|
507 | Example: load an image and align it so it looks as if anchored to the |
|
|
508 | background (that's exactly what C<rootalign> does btw.): |
|
|
509 | |
|
|
510 | move -TX, -TY, keep { load "mybg.png" } |
|
|
511 | |
|
|
512 | =item TW |
|
|
513 | |
|
|
514 | Return the width (C<TW>) and height (C<TH>) of the terminal window (the |
|
|
515 | terminal window is the full window by default, and the character area only |
|
|
516 | when in border-respect mode). |
|
|
517 | |
|
|
518 | Using these functions make your expression sensitive to window resizes. |
|
|
519 | |
|
|
520 | These functions are mainly useful to scale images, or to clip images to |
|
|
521 | the window size to conserve memory. |
|
|
522 | |
|
|
523 | Example: take the screen background, clip it to the window size, blur it a |
|
|
524 | bit, align it to the window position and use it as background. |
|
|
525 | |
|
|
526 | clip move -TX, -TY, keep { blur 5, root } |
|
|
527 | |
|
|
528 | =cut |
|
|
529 | |
|
|
530 | sub TX() { $frame->[FR_AGAIN]{position} = 1; $x } |
|
|
531 | sub TY() { $frame->[FR_AGAIN]{position} = 1; $y } |
|
|
532 | sub TW() { $frame->[FR_AGAIN]{size} = 1; $w } |
|
|
533 | sub TH() { $frame->[FR_AGAIN]{size} = 1; $h } |
|
|
534 | |
|
|
535 | =item now |
|
|
536 | |
|
|
537 | Returns the current time as (fractional) seconds since the epoch. |
|
|
538 | |
|
|
539 | Using this expression does I<not> make your expression sensitive to time, |
|
|
540 | but the next two functions do. |
|
|
541 | |
|
|
542 | =item again $seconds |
|
|
543 | |
|
|
544 | When this function is used the expression will be reevaluated again in |
|
|
545 | C<$seconds> seconds. |
|
|
546 | |
|
|
547 | Example: load some image and rotate it according to the time of day (as if it were |
|
|
548 | the hour pointer of a clock). Update this image every minute. |
|
|
549 | |
|
|
550 | again 60; |
|
|
551 | rotate 50, 50, (now % 86400) * -72 / 8640, scale keep { load "myclock.png" } |
|
|
552 | |
|
|
553 | =item counter $seconds |
|
|
554 | |
|
|
555 | Like C<again>, but also returns an increasing counter value, starting at |
|
|
556 | 0, which might be useful for some simple animation effects. |
|
|
557 | |
|
|
558 | =cut |
|
|
559 | |
|
|
560 | sub now() { urxvt::NOW } |
|
|
561 | |
|
|
562 | sub again($) { |
|
|
563 | $frame->[FR_AGAIN]{time} = $_[0]; |
|
|
564 | } |
|
|
565 | |
|
|
566 | sub counter($) { |
|
|
567 | $frame->[FR_AGAIN]{time} = $_[0]; |
|
|
568 | $frame->[FR_STATE]{counter} + 0 |
|
|
569 | } |
|
|
570 | |
|
|
571 | =back |
|
|
572 | |
|
|
573 | =head2 SHAPE CHANGING OPERATORS |
|
|
574 | |
|
|
575 | The following operators modify the shape, size or position of the image. |
|
|
576 | |
|
|
577 | =over 4 |
|
|
578 | |
|
|
579 | =item clip $img |
|
|
580 | |
|
|
581 | =item clip $width, $height, $img |
|
|
582 | |
|
|
583 | =item clip $x, $y, $width, $height, $img |
|
|
584 | |
|
|
585 | Clips an image to the given rectangle. If the rectangle is outside the |
|
|
586 | image area (e.g. when C<$x> or C<$y> are negative) or the rectangle is |
|
|
587 | larger than the image, then the tiling mode defines how the extra pixels |
|
|
588 | will be filled. |
|
|
589 | |
|
|
590 | If C<$x> an C<$y> are missing, then C<0> is assumed for both. |
|
|
591 | |
|
|
592 | If C<$width> and C<$height> are missing, then the window size will be |
|
|
593 | assumed. |
|
|
594 | |
|
|
595 | Example: load an image, blur it, and clip it to the window size to save |
|
|
596 | memory. |
|
|
597 | |
|
|
598 | clip keep { blur 10, load "mybg.png" } |
|
|
599 | |
|
|
600 | =cut |
|
|
601 | |
|
|
602 | sub clip($;$$;$$) { |
|
|
603 | my $img = pop; |
|
|
604 | my $h = pop || TH; |
|
|
605 | my $w = pop || TW; |
|
|
606 | $img->sub_rect ($_[0], $_[1], $w, $h) |
|
|
607 | } |
|
|
608 | |
|
|
609 | =item scale $img |
|
|
610 | |
|
|
611 | =item scale $size_factor, $img |
|
|
612 | |
|
|
613 | =item scale $width_factor, $height_factor, $img |
|
|
614 | |
|
|
615 | Scales the image by the given factors in horizontal |
|
|
616 | (C<$width>) and vertical (C<$height>) direction. |
|
|
617 | |
|
|
618 | If only one factor is give, it is used for both directions. |
|
|
619 | |
|
|
620 | If no factors are given, scales the image to the window size without |
|
|
621 | keeping aspect. |
|
|
622 | |
|
|
623 | =item resize $width, $height, $img |
|
|
624 | |
|
|
625 | Resizes the image to exactly C<$width> times C<$height> pixels. |
|
|
626 | |
|
|
627 | =item fit $img |
|
|
628 | |
|
|
629 | =item fit $width, $height, $img |
|
|
630 | |
|
|
631 | Fits the image into the given C<$width> and C<$height> without changing |
|
|
632 | aspect, or the terminal size. That means it will be shrunk or grown until |
|
|
633 | the whole image fits into the given area, possibly leaving borders. |
|
|
634 | |
|
|
635 | =item cover $img |
|
|
636 | |
|
|
637 | =item cover $width, $height, $img |
|
|
638 | |
|
|
639 | Similar to C<fit>, but shrinks or grows until all of the area is covered |
|
|
640 | by the image, so instead of potentially leaving borders, it will cut off |
|
|
641 | image data that doesn't fit. |
|
|
642 | |
|
|
643 | =cut |
|
|
644 | |
|
|
645 | sub scale($;$;$) { |
|
|
646 | my $img = pop; |
|
|
647 | |
|
|
648 | @_ == 2 ? $img->scale ($_[0] * $img->w, $_[1] * $img->h) |
|
|
649 | : @_ ? $img->scale ($_[0] * $img->w, $_[0] * $img->h) |
|
|
650 | : $img->scale (TW, TH) |
31 | } |
651 | } |
32 | |
652 | |
33 | sub resize($$$) { |
653 | sub resize($$$) { |
34 | $_[0]->scale ($_[1], $_[2]) |
654 | my $img = pop; |
|
|
655 | $img->scale ($_[0], $_[1]) |
35 | } |
656 | } |
36 | |
657 | |
|
|
658 | sub fit($;$$) { |
|
|
659 | my $img = pop; |
|
|
660 | my $w = ($_[0] || TW) / $img->w; |
|
|
661 | my $h = ($_[1] || TH) / $img->h; |
|
|
662 | scale +(min $w, $h), $img |
|
|
663 | } |
|
|
664 | |
|
|
665 | sub cover($;$$) { |
|
|
666 | my $img = pop; |
|
|
667 | my $w = ($_[0] || TW) / $img->w; |
|
|
668 | my $h = ($_[1] || TH) / $img->h; |
|
|
669 | scale +(max $w, $h), $img |
|
|
670 | } |
|
|
671 | |
|
|
672 | =item move $dx, $dy, $img |
|
|
673 | |
|
|
674 | Moves the image by C<$dx> pixels in the horizontal, and C<$dy> pixels in |
|
|
675 | the vertical. |
|
|
676 | |
|
|
677 | Example: move the image right by 20 pixels and down by 30. |
|
|
678 | |
|
|
679 | move 20, 30, ... |
|
|
680 | |
|
|
681 | =item align $xalign, $yalign, $img |
|
|
682 | |
|
|
683 | Aligns the image according to a factor - C<0> means the image is moved to |
|
|
684 | the left or top edge (for C<$xalign> or C<$yalign>), C<0.5> means it is |
|
|
685 | exactly centered and C<1> means it touches the right or bottom edge. |
|
|
686 | |
|
|
687 | Example: remove any visible border around an image, center it vertically but move |
|
|
688 | it to the right hand side. |
|
|
689 | |
|
|
690 | align 1, 0.5, pad $img |
|
|
691 | |
|
|
692 | =item center $img |
|
|
693 | |
|
|
694 | =item center $width, $height, $img |
|
|
695 | |
|
|
696 | Centers the image, i.e. the center of the image is moved to the center of |
|
|
697 | the terminal window (or the box specified by C<$width> and C<$height> if |
|
|
698 | given). |
|
|
699 | |
|
|
700 | Example: load an image and center it. |
|
|
701 | |
|
|
702 | center keep { pad load "mybg.png" } |
|
|
703 | |
|
|
704 | =item rootalign $img |
|
|
705 | |
|
|
706 | Moves the image so that it appears glued to the screen as opposed to the |
|
|
707 | window. This gives the illusion of a larger area behind the window. It is |
|
|
708 | exactly equivalent to C<move -TX, -TY>, that is, it moves the image to the |
|
|
709 | top left of the screen. |
|
|
710 | |
|
|
711 | Example: load a background image, put it in mirror mode and root align it. |
|
|
712 | |
|
|
713 | rootalign keep { mirror load "mybg.png" } |
|
|
714 | |
|
|
715 | Example: take the screen background and align it, giving the illusion of |
|
|
716 | transparency as long as the window isn't in front of other windows. |
|
|
717 | |
|
|
718 | rootalign root |
|
|
719 | |
|
|
720 | =cut |
|
|
721 | |
37 | sub move($$$) { |
722 | sub move($$;$) { |
38 | # TODO: must be simpler |
723 | my $img = pop->clone; |
39 | $_[0]->transform ($_[0]->w, $_[0]->h, $_[1], |
724 | $img->move ($_[0], $_[1]); |
40 | 1, 0, -$_[2], |
725 | $img |
41 | 0, 1, -$_[3], |
726 | } |
42 | 0, 0, 1, |
727 | |
|
|
728 | sub align($;$$) { |
|
|
729 | my $img = pop; |
|
|
730 | |
|
|
731 | move $_[0] * (TW - $img->w), |
|
|
732 | $_[1] * (TH - $img->h), |
|
|
733 | $img |
|
|
734 | } |
|
|
735 | |
|
|
736 | sub center($;$$) { |
|
|
737 | my $img = pop; |
|
|
738 | my $w = $_[0] || TW; |
|
|
739 | my $h = $_[1] || TH; |
|
|
740 | |
|
|
741 | move 0.5 * ($w - $img->w), 0.5 * ($h - $img->h), $img |
|
|
742 | } |
|
|
743 | |
|
|
744 | sub rootalign($) { |
|
|
745 | move -TX, -TY, $_[0] |
|
|
746 | } |
|
|
747 | |
|
|
748 | =item rotate $center_x, $center_y, $degrees, $img |
|
|
749 | |
|
|
750 | Rotates the image clockwise by C<$degrees> degrees, around the point at |
|
|
751 | C<$center_x> and C<$center_y> (specified as factor of image width/height). |
|
|
752 | |
|
|
753 | Example: rotate the image by 90 degrees around it's center. |
|
|
754 | |
|
|
755 | rotate 0.5, 0.5, 90, keep { load "$HOME/mybg.png" } |
|
|
756 | |
|
|
757 | =cut |
|
|
758 | |
|
|
759 | sub rotate($$$$) { |
|
|
760 | my $img = pop; |
|
|
761 | $img->rotate ( |
|
|
762 | $_[0] * ($img->w + $img->x), |
|
|
763 | $_[1] * ($img->h + $img->y), |
|
|
764 | $_[2] * (3.14159265 / 180), |
43 | ) |
765 | ) |
44 | } |
766 | } |
45 | |
767 | |
|
|
768 | =back |
|
|
769 | |
|
|
770 | =head2 COLOUR MODIFICATIONS |
|
|
771 | |
|
|
772 | The following operators change the pixels of the image. |
|
|
773 | |
|
|
774 | =over 4 |
|
|
775 | |
|
|
776 | =item tint $color, $img |
|
|
777 | |
|
|
778 | Tints the image in the given colour. |
|
|
779 | |
|
|
780 | Example: tint the image red. |
|
|
781 | |
|
|
782 | tint "red", load "rgb.png" |
|
|
783 | |
|
|
784 | Example: the same, but specify the colour by component. |
|
|
785 | |
|
|
786 | tint [1, 0, 0], load "rgb.png" |
|
|
787 | |
|
|
788 | =cut |
|
|
789 | |
46 | sub rotate($$$$) { |
790 | sub tint($$) { |
47 | $_[0]->rotate ($_[0], $_[1], $_[2], $_[3] * (3.14159265 / 180)) |
791 | $_[1]->tint ($_[0]) |
48 | } |
792 | } |
49 | |
793 | |
50 | sub blur($$$) { |
794 | =item contrast $factor, $img |
51 | my ($img, $rh, $rv) = @_; |
|
|
52 | |
795 | |
53 | $img = $img->clone; |
796 | =item contrast $r, $g, $b, $img |
54 | $img->clone->blur ($rh, $rv); |
797 | |
55 | $img |
798 | =item contrast $r, $g, $b, $a, $img |
56 | } |
799 | |
|
|
800 | Adjusts the I<contrast> of an image. |
|
|
801 | |
|
|
802 | The first form applies a single C<$factor> to red, green and blue, the |
|
|
803 | second form applies separate factors to each colour channel, and the last |
|
|
804 | form includes the alpha channel. |
|
|
805 | |
|
|
806 | Values from 0 to 1 lower the contrast, values higher than 1 increase the |
|
|
807 | contrast. |
|
|
808 | |
|
|
809 | Due to limitations in the underlying XRender extension, lowering contrast |
|
|
810 | also reduces brightness, while increasing contrast currently also |
|
|
811 | increases brightness. |
|
|
812 | |
|
|
813 | =item brightness $bias, $img |
|
|
814 | |
|
|
815 | =item brightness $r, $g, $b, $img |
|
|
816 | |
|
|
817 | =item brightness $r, $g, $b, $a, $img |
|
|
818 | |
|
|
819 | Adjusts the brightness of an image. |
|
|
820 | |
|
|
821 | The first form applies a single C<$bias> to red, green and blue, the |
|
|
822 | second form applies separate biases to each colour channel, and the last |
|
|
823 | form includes the alpha channel. |
|
|
824 | |
|
|
825 | Values less than 0 reduce brightness, while values larger than 0 increase |
|
|
826 | it. Useful range is from -1 to 1 - the former results in a black, the |
|
|
827 | latter in a white picture. |
|
|
828 | |
|
|
829 | Due to idiosyncrasies in the underlying XRender extension, biases less |
|
|
830 | than zero can be I<very> slow. |
|
|
831 | |
|
|
832 | =cut |
57 | |
833 | |
58 | sub contrast($$;$$;$) { |
834 | sub contrast($$;$$;$) { |
|
|
835 | my $img = pop; |
59 | my ($img, $r, $g, $b, $a) = @_; |
836 | my ($r, $g, $b, $a) = @_; |
|
|
837 | |
60 | ($g, $b) = ($r, $r) if @_ < 4; |
838 | ($g, $b) = ($r, $r) if @_ < 3; |
61 | $a = 1 if @_ < 5; |
839 | $a = 1 if @_ < 4; |
|
|
840 | |
62 | $img = $img->clone; |
841 | $img = $img->clone; |
63 | $img->contrast ($r, $g, $b, $a); |
842 | $img->contrast ($r, $g, $b, $a); |
64 | $img |
843 | $img |
65 | } |
844 | } |
66 | |
845 | |
67 | sub brightness($$;$$;$) { |
846 | sub brightness($$;$$;$) { |
|
|
847 | my $img = pop; |
68 | my ($img, $r, $g, $b, $a) = @_; |
848 | my ($r, $g, $b, $a) = @_; |
|
|
849 | |
69 | ($g, $b) = ($r, $r) if @_ < 4; |
850 | ($g, $b) = ($r, $r) if @_ < 3; |
70 | $a = 1 if @_ < 5; |
851 | $a = 1 if @_ < 4; |
|
|
852 | |
71 | $img = $img->clone; |
853 | $img = $img->clone; |
72 | $img->brightness ($r, $g, $b, $a); |
854 | $img->brightness ($r, $g, $b, $a); |
73 | $img |
855 | $img |
74 | } |
856 | } |
75 | |
857 | |
76 | sub x() { $new->{position_sensitive} = 1; $x } |
858 | =item blur $radius, $img |
77 | sub y() { $new->{position_sensitive} = 1; $y } |
|
|
78 | sub w() { $new->{size_sensitive} = 1; $w } |
|
|
79 | sub h() { $new->{size_sensitive} = 1; $h } |
|
|
80 | sub now() { urxvt::NOW } |
|
|
81 | |
859 | |
82 | sub again($) { |
860 | =item blur $radius_horz, $radius_vert, $img |
83 | $new->{again} = $_[0]; |
861 | |
|
|
862 | Gaussian-blurs the image with (roughly) C<$radius> pixel radius. The radii |
|
|
863 | can also be specified separately. |
|
|
864 | |
|
|
865 | Blurring is often I<very> slow, at least compared or other |
|
|
866 | operators. Larger blur radii are slower than smaller ones, too, so if you |
|
|
867 | don't want to freeze your screen for long times, start experimenting with |
|
|
868 | low values for radius (<5). |
|
|
869 | |
|
|
870 | =cut |
|
|
871 | |
|
|
872 | sub blur($$;$) { |
|
|
873 | my $img = pop; |
|
|
874 | $img->blur ($_[0], @_ >= 2 ? $_[1] : $_[0]) |
|
|
875 | } |
|
|
876 | |
|
|
877 | =back |
|
|
878 | |
|
|
879 | =head2 OTHER STUFF |
|
|
880 | |
|
|
881 | Anything that didn't fit any of the other categories, even after applying |
|
|
882 | force and closing our eyes. |
|
|
883 | |
|
|
884 | =over 4 |
|
|
885 | |
|
|
886 | =item keep { ... } |
|
|
887 | |
|
|
888 | This operator takes a code block as argument, that is, one or more |
|
|
889 | statements enclosed by braces. |
|
|
890 | |
|
|
891 | The trick is that this code block is only evaluated when the outcome |
|
|
892 | changes - on other calls the C<keep> simply returns the image it computed |
|
|
893 | previously (yes, it should only be used with images). Or in other words, |
|
|
894 | C<keep> I<caches> the result of the code block so it doesn't need to be |
|
|
895 | computed again. |
|
|
896 | |
|
|
897 | This can be extremely useful to avoid redoing slow operations - for |
|
|
898 | example, if your background expression takes the root background, blurs it |
|
|
899 | and then root-aligns it it would have to blur the root background on every |
|
|
900 | window move or resize. |
|
|
901 | |
|
|
902 | Another example is C<load>, which can be quite slow. |
|
|
903 | |
|
|
904 | In fact, urxvt itself encloses the whole expression in some kind of |
|
|
905 | C<keep> block so it only is reevaluated as required. |
|
|
906 | |
|
|
907 | Putting the blur into a C<keep> block will make sure the blur is only done |
|
|
908 | once, while the C<rootalign> is still done each time the window moves. |
|
|
909 | |
|
|
910 | rootalign keep { blur 10, root } |
|
|
911 | |
|
|
912 | This leaves the question of how to force reevaluation of the block, |
|
|
913 | in case the root background changes: If expression inside the block |
|
|
914 | is sensitive to some event (root background changes, window geometry |
|
|
915 | changes), then it will be reevaluated automatically as needed. |
|
|
916 | |
|
|
917 | =cut |
|
|
918 | |
|
|
919 | sub keep(&) { |
|
|
920 | my $id = $_[0]+0; |
|
|
921 | |
|
|
922 | local $frame = $self->{frame_cache}{$id} ||= [$frame]; |
|
|
923 | |
|
|
924 | unless ($frame->[FR_CACHE]) { |
|
|
925 | $frame->[FR_CACHE] = [ $_[0]() ]; |
|
|
926 | |
|
|
927 | my $self = $self; |
|
|
928 | my $frame = $frame; |
|
|
929 | Scalar::Util::weaken $frame; |
|
|
930 | $self->compile_frame ($frame, sub { |
|
|
931 | # clear this frame cache, also for all parents |
|
|
932 | for (my $frame = $frame; $frame; $frame = $frame->[0]) { |
|
|
933 | undef $frame->[FR_CACHE]; |
|
|
934 | } |
|
|
935 | |
|
|
936 | $self->recalculate; |
|
|
937 | }); |
|
|
938 | }; |
|
|
939 | |
|
|
940 | # in scalar context we always return the first original result, which |
|
|
941 | # is not quite how perl works. |
|
|
942 | wantarray |
|
|
943 | ? @{ $frame->[FR_CACHE] } |
|
|
944 | : $frame->[FR_CACHE][0] |
|
|
945 | } |
|
|
946 | |
|
|
947 | # sub keep_clear() { |
|
|
948 | # delete $self->{frame_cache}; |
84 | } |
949 | # } |
85 | |
950 | |
86 | sub counter($) { |
951 | =back |
87 | $new->{again} = $_[0]; |
952 | |
88 | $self->{counter}++ + 0 |
953 | =cut |
89 | } |
954 | |
90 | } |
955 | } |
91 | |
956 | |
92 | sub parse_expr { |
957 | sub parse_expr { |
93 | my $expr = eval "sub {\npackage urxvt::bgdsl;\n#line 0 'background expression'\n$_[0]\n}"; |
958 | my $expr = eval |
|
|
959 | "sub {\n" |
|
|
960 | . "package urxvt::bgdsl;\n" |
|
|
961 | . "#line 0 'background expression'\n" |
|
|
962 | . "$_[0]\n" |
|
|
963 | . "}"; |
94 | die if $@; |
964 | die if $@; |
95 | $expr |
965 | $expr |
96 | } |
966 | } |
97 | |
967 | |
98 | # compiles a parsed expression |
968 | # compiles a parsed expression |
99 | sub set_expr { |
969 | sub set_expr { |
100 | my ($self, $expr) = @_; |
970 | my ($self, $expr) = @_; |
101 | |
971 | |
102 | local $Data::Dumper::Deparse=1; use Data::Dumper; warn Dumper $expr;#d# |
972 | $self->{root} = []; # the outermost frame |
103 | $self->{expr} = $expr; |
973 | $self->{expr} = $expr; |
104 | $self->recalculate; |
974 | $self->recalculate; |
105 | } |
975 | } |
106 | |
976 | |
|
|
977 | # takes a hash of sensitivity indicators and installs watchers |
|
|
978 | sub compile_frame { |
|
|
979 | my ($self, $frame, $cb) = @_; |
|
|
980 | |
|
|
981 | my $state = $frame->[urxvt::bgdsl::FR_STATE] ||= {}; |
|
|
982 | my $again = $frame->[urxvt::bgdsl::FR_AGAIN]; |
|
|
983 | |
|
|
984 | # don't keep stuff alive |
|
|
985 | Scalar::Util::weaken $state; |
|
|
986 | |
|
|
987 | if ($again->{nested}) { |
|
|
988 | $state->{nested} = 1; |
|
|
989 | } else { |
|
|
990 | delete $state->{nested}; |
|
|
991 | } |
|
|
992 | |
|
|
993 | if (my $interval = $again->{time}) { |
|
|
994 | $state->{time} = [$interval, urxvt::timer->new->after ($interval)->interval ($interval)] |
|
|
995 | if $state->{time}[0] != $interval; |
|
|
996 | |
|
|
997 | # callback *might* have changed, although we could just rule that out |
|
|
998 | $state->{time}[1]->cb (sub { |
|
|
999 | ++$state->{counter}; |
|
|
1000 | $cb->(); |
|
|
1001 | }); |
|
|
1002 | } else { |
|
|
1003 | delete $state->{time}; |
|
|
1004 | } |
|
|
1005 | |
|
|
1006 | if ($again->{position}) { |
|
|
1007 | $state->{position} = $self->on (position_change => $cb); |
|
|
1008 | } else { |
|
|
1009 | delete $state->{position}; |
|
|
1010 | } |
|
|
1011 | |
|
|
1012 | if ($again->{size}) { |
|
|
1013 | $state->{size} = $self->on (size_change => $cb); |
|
|
1014 | } else { |
|
|
1015 | delete $state->{size}; |
|
|
1016 | } |
|
|
1017 | |
|
|
1018 | if ($again->{rootpmap}) { |
|
|
1019 | $state->{rootpmap} = $self->on (rootpmap_change => $cb); |
|
|
1020 | } else { |
|
|
1021 | delete $state->{rootpmap}; |
|
|
1022 | } |
|
|
1023 | } |
|
|
1024 | |
107 | # evaluate the current bg expression |
1025 | # evaluate the current bg expression |
108 | sub recalculate { |
1026 | sub recalculate { |
109 | my ($self) = @_; |
1027 | my ($arg_self) = @_; |
110 | |
1028 | |
111 | local $urxvt::bgdsl::vars::self = $self; |
1029 | # rate limit evaluation |
112 | |
1030 | |
113 | local $urxvt::bgdsl::vars::old = $self->{state}; |
1031 | if ($arg_self->{next_refresh} > urxvt::NOW) { |
114 | local $urxvt::bgdsl::vars::new = my $state = $self->{state} = {}; |
1032 | $arg_self->{next_refresh_timer} = urxvt::timer->new->after ($arg_self->{next_refresh} - urxvt::NOW)->cb (sub { |
|
|
1033 | $arg_self->recalculate; |
|
|
1034 | }); |
|
|
1035 | return; |
|
|
1036 | } |
115 | |
1037 | |
116 | ($urxvt::bgdsl::vars::x, $urxvt::bgdsl::vars::y, $urxvt::bgdsl::vars::w, $urxvt::bgdsl::vars::h) = |
1038 | $arg_self->{next_refresh} = urxvt::NOW + $MIN_INTERVAL; |
117 | $self->get_geometry; |
|
|
118 | |
1039 | |
|
|
1040 | # set environment to evaluate user expression |
|
|
1041 | |
|
|
1042 | local $self = $arg_self; |
|
|
1043 | local $HOME = $ENV{HOME}; |
|
|
1044 | local $frame = $self->{root}; |
|
|
1045 | |
|
|
1046 | ($x, $y, $w, $h) = $self->background_geometry ($self->{border}); |
|
|
1047 | |
|
|
1048 | # evaluate user expression |
|
|
1049 | |
119 | my $img = eval { $self->{expr}->() }; |
1050 | my @img = eval { $self->{expr}->() }; |
120 | warn $@ if $@;#d# |
1051 | die $@ if $@; |
|
|
1052 | die "background-expr did not return anything.\n" unless @img; |
|
|
1053 | die "background-expr: expected image(s), got something else.\n" |
|
|
1054 | if grep { !UNIVERSAL::isa $_, "urxvt::img" } @img; |
121 | |
1055 | |
122 | my $repeat; |
1056 | my $img = urxvt::bgdsl::merge @img; |
123 | |
1057 | |
124 | if (my $again = $state->{again}) { |
1058 | $frame->[FR_AGAIN]{size} = 1 |
125 | $repeat = 1; |
1059 | if $img->repeat_mode != urxvt::RepeatNormal; |
126 | $state->{again} = urxvt::timer->new->after ($again)->cb (sub { $self->recalculate }); |
1060 | |
|
|
1061 | # if the expression is sensitive to external events, prepare reevaluation then |
|
|
1062 | $self->compile_frame ($frame, sub { $arg_self->recalculate }); |
|
|
1063 | |
|
|
1064 | # clear stuff we no longer need |
|
|
1065 | |
|
|
1066 | # unless (%{ $frame->[FR_STATE] }) { |
|
|
1067 | # delete $self->{state}; |
|
|
1068 | # delete $self->{expr}; |
127 | } |
1069 | # } |
128 | |
1070 | |
129 | if (delete $state->{position_sensitive}) { |
1071 | # set background pixmap |
130 | $repeat = 1; |
|
|
131 | $self->enable (position_change => sub { $_[0]->recalculate }); |
|
|
132 | } else { |
|
|
133 | $self->disable ("position_change"); |
|
|
134 | } |
|
|
135 | |
1072 | |
136 | if (delete $state->{size_sensitive}) { |
|
|
137 | $repeat = 1; |
|
|
138 | $self->enable (size_change => sub { $_[0]->recalculate }); |
|
|
139 | } else { |
|
|
140 | $self->disable ("size_change"); |
|
|
141 | } |
|
|
142 | |
|
|
143 | # TODO: install handlers for geometry changes &c |
|
|
144 | |
|
|
145 | warn $img; |
|
|
146 | $self->set_background ($img); |
1073 | $self->set_background ($img, $self->{border}); |
147 | $self->scr_recolour (0); |
1074 | $self->scr_recolour (0); |
148 | $self->want_refresh; |
1075 | $self->want_refresh; |
149 | } |
1076 | } |
150 | |
1077 | |
151 | sub on_start { |
1078 | sub on_start { |
152 | my ($self) = @_; |
1079 | my ($self) = @_; |
153 | |
1080 | |
|
|
1081 | my $expr = $self->x_resource ("%.expr") |
|
|
1082 | or return; |
|
|
1083 | |
|
|
1084 | $self->has_render |
|
|
1085 | or die "background extension needs RENDER extension 0.10 or higher, ignoring background-expr.\n"; |
|
|
1086 | |
154 | $self->set_expr (parse_expr $EXPR); |
1087 | $self->set_expr (parse_expr $expr); |
|
|
1088 | $self->{border} = $self->x_resource_boolean ("%.border"); |
|
|
1089 | |
|
|
1090 | $MIN_INTERVAL = $self->x_resource ("%.interval"); |
155 | |
1091 | |
156 | () |
1092 | () |
157 | } |
1093 | } |
158 | |
1094 | |