color.RGBA has two problems with regards to using it.
First the color values need to be premultiplied, whereas most APIs
have non-premultiplied values. This is mainly to preserve color components
with low alpha values.
Second there are two ways to premultiply with sRGB. One is to premultiply
after sRGB conversion, the other is before. This makes using the API more
confusing.
Using color.NRGBA in sRGB makes it align with CSS.e
Signed-off-by: Egon Elbre <egonelbre@gmail.com>
PaintOp.Rect is the wrong abstraction; it implies a clip operation
better handled by package clip, and not all paints need it (colors).
Furthermore, it's awkward to specify a PaintOp that fills up the
current clip area, regardless of its size.
Redefine PathOp to mean "fill current clip area".
API change. Replace uses of PaintOp.Rect with a TransformOp applied
before the PaintOp.
Leave a TODO for the PathOp infinity area.
Fixes gio#167
Signed-off-by: Elias Naur <mail@eliasnaur.com>
We're about to remove PaintOp.Rect. Replacing PaintOps with Fill or
FillShape where possible will ease the transition.
Using Fill in tests exposed a problem with the infinity in paint.Fill.
Adjust it for now; it will be removed later.
Updates gio#167
Signed-off-by: Elias Naur <mail@eliasnaur.com>
Uses app/headless to create a set of test cases for drawing operations, including clipping
textures and transforms. This commit tests for approximate pixel matches, if future changes affect
local drawing operations it will be easy to change the reference images, it thus becomes and
should be an intentional operation if changes lead to local changes in drawn results.
Ideally we should be able to make the tests check for exact pixel matches down the line to ensure
consistent results between platforms.
Signed-off-by: Viktor <viktor.ogeman@gmail.com>
Walter Werner SCHNEIDER