impl SkRuntimeColorFilter::getFlags()
Simply build the skvm program and look to see if in.a.id == out.a.id.
This obviously is conservative, with false negatives possible. I
haven't done it here, but one possible improvement is to splat uniforms
so constant folding can peer through uniforms too.
Add some basic tests.
Change-Id: I5578ba38ff490b96bf84538025e08d9d352f0320
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/370825
Commit-Queue: Mike Klein <mtklein@google.com>
Reviewed-by: Brian Osman <brianosman@google.com>
diff --git a/tests/SkRuntimeEffectTest.cpp b/tests/SkRuntimeEffectTest.cpp
index 8525e7e..46f4836 100644
--- a/tests/SkRuntimeEffectTest.cpp
+++ b/tests/SkRuntimeEffectTest.cpp
@@ -442,3 +442,23 @@
DEF_GPUTEST_FOR_RENDERING_CONTEXTS(SkRuntimeStructNameReuse_GPU, r, ctxInfo) {
test_RuntimeEffectStructNameReuse(r, ctxInfo.directContext());
}
+
+DEF_TEST(SkRuntimeColorFilterFlags, r) {
+ { // Here's a non-trivial filter that doesn't change alpha.
+ auto [effect, err] = SkRuntimeEffect::Make(SkString{
+ "uniform shader input; half4 main() { return sample(input) + half4(1,1,1,0); }"});
+ REPORTER_ASSERT(r, effect && err.isEmpty());
+ sk_sp<SkColorFilter> input = nullptr,
+ filter = effect->makeColorFilter(SkData::MakeEmpty(), &input, 1);
+ REPORTER_ASSERT(r, filter && filter->isAlphaUnchanged());
+ }
+
+ { // Here's one that definitely changes alpha.
+ auto [effect, err] = SkRuntimeEffect::Make(SkString{
+ "uniform shader input; half4 main() { return sample(input) + half4(0,0,0,4); }"});
+ REPORTER_ASSERT(r, effect && err.isEmpty());
+ sk_sp<SkColorFilter> input = nullptr,
+ filter = effect->makeColorFilter(SkData::MakeEmpty(), &input, 1);
+ REPORTER_ASSERT(r, filter && !filter->isAlphaUnchanged());
+ }
+}