blob: aba5b6c74cba987a1ddff05f386652e6716eb334 [file] [log] [blame]
/*
* Copyright 2018 Google Inc.
*
* Use of this source code is governed by a BSD-style license that can be
* found in the LICENSE file.
*/
// Provides tiling for the repeat or mirror modes.
in fragmentProcessor colorizer;
in fragmentProcessor gradLayout;
layout(key) in bool mirror;
layout(key) in bool makePremul;
// Trust the creator that this matches the color spec of the gradient
in bool colorsAreOpaque;
void main() {
half4 t = sample(gradLayout);
if (!gradLayout.preservesOpaqueInput && t.y < 0) {
// layout has rejected this fragment (rely on sksl to remove this branch if the layout FP
// preserves opacity is false)
sk_OutColor = half4(0);
} else {
@if(mirror) {
half t_1 = t.x - 1;
half tiled_t = t_1 - 2 * floor(t_1 * 0.5) - 1;
if (sk_Caps.mustDoOpBetweenFloorAndAbs) {
// At this point the expected value of tiled_t should between -1 and 1, so this
// clamp has no effect other than to break up the floor and abs calls and make sure
// the compiler doesn't merge them back together.
tiled_t = clamp(tiled_t, -1, 1);
}
t.x = abs(tiled_t);
} else {
// Simple repeat mode
t.x = fract(t.x);
}
// t.x has been tiled (repeat or mirrored), but pass through remaining 3 components
// unmodified.
sk_OutColor = sample(colorizer, t);
}
@if (makePremul) {
sk_OutColor.xyz *= sk_OutColor.w;
}
}
//////////////////////////////////////////////////////////////////////////////
// If the layout does not preserve opacity, remove the opaque optimization,
// but otherwise respect the provided color opacity state.
@optimizationFlags {
kCompatibleWithCoverageAsAlpha_OptimizationFlag |
(colorsAreOpaque && gradLayout->preservesOpaqueInput() ? kPreservesOpaqueInput_OptimizationFlag
: kNone_OptimizationFlags)
}