split up sample canvas and brush shaders

1 files changed, 25 insertions, 0 deletions

diff --git a/doc/shaders/util.txt b/doc/shaders/util.txt
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+SHADER UTILITIES
+================
+
+These are little snippets which may be useful in writing your own shaders.
+
+
+
+>> basic way to slow the frame rate of a shader.
+
+window.zz=window.zz||0
+if(!(x+y)) zz++
+if (lex.bg != 1 && !(zz % 4)) {
+  ...
+}
+
+
+>> handy for brushes - use color to mask brush shape
+
+lex.opacity = lex.bg == colors.black ? 0 : 1
+
+
+Tip: Set to "animate brush", then use option+shift (alt+shift) to
+copy color from the canvas. Brush will have the "shape" of the
+copied color only.  Can be a cool effect when used with fg/bg only.
+