Add unit tests for back-and-forth conversions through sRGB and Rec. 709 gamma.

diff --git a/effect_chain_test.cpp b/effect_chain_test.cpp
index 0161a92cf6b6a15ee8c37c7a7319fa5618af013e..20fd9bc97395672921b05f677f34efdf0d35762b 100644 (file)
--- a/effect_chain_test.cpp
+++ b/effect_chain_test.cpp
@@ -80,3 +80,32 @@ TEST(MirrorTest, BasicTest) {
 
        expect_equal(expected_data, out_data, 3, 2);
 }
+
+// The identity effect needs linear light, and thus will get conversions on both sides.
+// Verify that sRGB data is properly converted to and from linear light for the entire ramp.
+TEST(EffectChainTest, IdentityThroughsRGBConversions) {
+       float data[256];
+       for (unsigned i = 0; i < 256; ++i) {
+               data[i] = i / 255.0;
+       };
+       float out_data[256];
+       EffectChainTester tester(data, 256, 1, FORMAT_GRAYSCALE, COLORSPACE_sRGB, GAMMA_sRGB);
+       tester.get_chain()->add_effect(new IdentityEffect());
+       tester.run(out_data, GL_RED, COLORSPACE_sRGB, GAMMA_sRGB);
+
+       expect_equal(data, out_data, 256, 1);
+}
+
+// Same, for the Rec. 601/709 gamma curve.
+TEST(EffectChainTest, IdentityThroughRec709) {
+       float data[256];
+       for (unsigned i = 0; i < 256; ++i) {
+               data[i] = i / 255.0;
+       };
+       float out_data[256];
+       EffectChainTester tester(data, 256, 1, FORMAT_GRAYSCALE, COLORSPACE_sRGB, GAMMA_REC_709);
+       tester.get_chain()->add_effect(new IdentityEffect());
+       tester.run(out_data, GL_RED, COLORSPACE_sRGB, GAMMA_REC_709);
+
+       expect_equal(data, out_data, 256, 1);
+}