skia2/tests/sksl/shared/Switch.metal
John Stiles ed2babaf94 Reland "Add switch statement support to PipelineStage."
This is a reland of be056f4f62

The Switch test has been restructured to dodge an iOS bug.

Original change's description:
> Add switch statement support to PipelineStage.
>
> This allows us to write SKSL_TEST_ES3 tests in SkSLTest and have them
> run properly. Previously, such a test would assert inside the pipeline-
> stage generator. In ES2 mode, we will rewrite switches as chained ifs,
> but in ES3 mode we will want to continue emitting them as-is (they will
> be faster than chained ifs on a modern GPU).
>
> `writeSwitchStatement` is adapted from GLSLCodeGenerator.
>
> Change-Id: I532ea5ed49869e7cdffced0cdcd0e353af8d4d79
> Bug: skia:12450
> Reviewed-on: https://skia-review.googlesource.com/c/skia/+/450478
> Commit-Queue: John Stiles <johnstiles@google.com>
> Commit-Queue: Brian Osman <brianosman@google.com>
> Auto-Submit: John Stiles <johnstiles@google.com>
> Reviewed-by: Brian Osman <brianosman@google.com>

Bug: skia:12450
Change-Id: I5102081c636ef09cd23f5bc894e6c96e92a4c121
Reviewed-on: https://skia-review.googlesource.com/c/skia/+/450757
Reviewed-by: Ethan Nicholas <ethannicholas@google.com>
Commit-Queue: John Stiles <johnstiles@google.com>
2021-09-21 13:07:50 +00:00

31 lines
760 B
Metal

#include <metal_stdlib>
#include <simd/simd.h>
using namespace metal;
struct Uniforms {
float4 colorGreen;
float4 colorRed;
};
struct Inputs {
};
struct Outputs {
float4 sk_FragColor [[color(0)]];
};
fragment Outputs fragmentMain(Inputs _in [[stage_in]], constant Uniforms& _uniforms [[buffer(0)]], bool _frontFacing [[front_facing]], float4 _fragCoord [[position]]) {
Outputs _out;
(void)_out;
float4 color;
switch (int(_uniforms.colorGreen.y)) {
case 0:
color = _uniforms.colorRed;
break;
case 1:
color = _uniforms.colorGreen;
break;
default:
color = _uniforms.colorRed;
break;
}
_out.sk_FragColor = color;
return _out;
}