+// A compute shader to mirror the inputs, in 2x2 blocks.
+class MirrorComputeEffect : public Effect {
+public:
+ MirrorComputeEffect() {}
+ string effect_type_id() const override { return "MirrorComputeEffect"; }
+ bool is_compute_shader() const override { return true; }
+ string output_fragment_shader() override { return read_file("mirror.comp"); }
+ void get_compute_dimensions(unsigned output_width, unsigned output_height,
+ unsigned *x, unsigned *y, unsigned *z) const override {
+ *x = output_width / 2;
+ *y = output_height / 2;
+ *z = 1;
+ }
+};
+
+TEST(ComputeShaderTest, Mirror) {
+ float data[] = {
+ 0.0f, 0.25f, 0.3f, 0.8f,
+ 0.75f, 1.0f, 1.0f, 0.2f,
+ };
+ float expected_data[] = {
+ 0.8f, 0.3f, 0.25f, 0.0f,
+ 0.2f, 1.0f, 1.0f, 0.75f,
+ };
+ float out_data[8];
+ EffectChainTester tester(data, 4, 2, FORMAT_GRAYSCALE, COLORSPACE_sRGB, GAMMA_LINEAR);
+ tester.get_chain()->add_effect(new MirrorComputeEffect());
+ tester.get_chain()->add_effect(new OneToOneEffect());
+ tester.run(out_data, GL_RED, COLORSPACE_sRGB, GAMMA_LINEAR);
+
+ expect_equal(expected_data, out_data, 4, 2);
+}
+