Fix alpha handling with sRGB textures.

[movit] / flat_input_test.cpp

diff --git a/flat_input_test.cpp b/flat_input_test.cpp
index 17ee9ce49f407abefc9206df05e1e69559f73c2f..b717764dda03bb136ff7cb3ece897fa04f3c2f43 100644 (file)
--- a/flat_input_test.cpp
+++ b/flat_input_test.cpp
@@ -77,6 +77,37 @@ TEST(FlatInput, RGBA) {
        expect_equal(expected_data, out_data, 4, size);
 }
 
+// Note: The sRGB conversion itself is tested in EffectChainTester,
+// since it also wants to test the chain building itself.
+// Here, we merely test that alpha is left alone; the test will usually
+// run using the sRGB OpenGL extension, but might be run with a
+// GammaExpansionEffect if the card/driver happens not to support that.
+TEST(FlatInput, AlphaIsNotModifiedBySRGBConversion) {
+       const int size = 5;
+
+       unsigned char data[4 * size] = {
+               0, 0, 0, 0,
+               0, 0, 0, 63,
+               0, 0, 0, 127,
+               0, 0, 0, 191,
+               0, 0, 0, 255,
+       };
+       float expected_data[4 * size] = {
+               0, 0, 0, 0.0 / 255.0,
+               0, 0, 0, 63.0 / 255.0,
+               0, 0, 0, 127.0 / 255.0,
+               0, 0, 0, 191.0 / 255.0,
+               0, 0, 0, 255.0 / 255.0,
+       };
+       float out_data[4 * size];
+
+        EffectChainTester tester(NULL, 1, size);
+        tester.add_input(data, FORMAT_RGBA, COLORSPACE_sRGB, GAMMA_sRGB);
+       tester.run(out_data, GL_RGBA, COLORSPACE_sRGB, GAMMA_LINEAR);
+
+       expect_equal(expected_data, out_data, 4, size);
+}
+
 TEST(FlatInput, BGR) {
        const int size = 5;