update dox for SkAvoidXfermode (as best I could)
fix 565 and 4444 implementations
git-svn-id: http://skia.googlecode.com/svn/trunk@420 2bbb7eff-a529-9590-31e7-b0007b416f81
diff --git a/include/effects/SkAvoidXfermode.h b/include/effects/SkAvoidXfermode.h
index 32bc049..2803c07 100644
--- a/include/effects/SkAvoidXfermode.h
+++ b/include/effects/SkAvoidXfermode.h
@@ -31,16 +31,21 @@
kTargetColor_Mode //!< draw only on top of the opColor
};
- /** This xfermode will draw the src everywhere except on top of the opColor
- or, depending on the Mode, draw only on top of the opColor.
- @param opColor the color to avoid (or to target depending on Mode).
- note: the alpha in opColor is ignored
- @param tolerance How closely we compare a pixel to the opColor.
- 0 - only operate if exact match
- 255 - maximum gradation (blending) based on how
- similar the pixel is to our opColor (max tolerance)
- @param mode If we should avoid or target the opColor
- */
+ /** This xfermode draws, or doesn't draw, based on the destination's
+ distance from an op-color.
+
+ There are two modes, and each mode interprets a tolerance value.
+
+ Avoid: In this mode, drawing is allowed only on destination pixels that
+ are different from the op-color.
+ Tolerance near 0: avoid anything close to the op-color
+ Tolerance near 255: avoid only colors very close to the op-color
+
+ Target: In this mode, drawing only occurs on destination pixels that
+ are similar to the op-color
+ Tolerance near 0: draw on colors that are very close to op-color
+ Tolerance near 255: draw on colors that to the op-color
+ */
SkAvoidXfermode(SkColor opColor, U8CPU tolerance, Mode mode);
// overrides from SkXfermode