+TEST(ResampleEffectTest, ReadWholePixelFromLeft) {
+ const int size = 5;
+
+ float data[size * size] = {
+ 0.0, 0.0, 0.0, 0.0, 0.0,
+ 0.0, 0.0, 0.0, 0.0, 0.0,
+ 0.0, 0.0, 1.0, 0.0, 0.0,
+ 0.0, 0.0, 0.0, 0.0, 0.0,
+ 0.0, 0.0, 0.0, 0.0, 0.0,
+ };
+ float expected_data[size * size] = {
+ 0.0, 0.0, 0.0, 0.0, 0.0,
+ 0.0, 0.0, 0.0, 0.0, 0.0,
+ 0.0, 1.0, 0.0, 0.0, 0.0,
+ 0.0, 0.0, 0.0, 0.0, 0.0,
+ 0.0, 0.0, 0.0, 0.0, 0.0,
+ };
+ float out_data[size * size];
+
+ EffectChainTester tester(data, size, size, FORMAT_GRAYSCALE, COLORSPACE_sRGB, GAMMA_LINEAR);
+ Effect *resample_effect = tester.get_chain()->add_effect(new ResampleEffect());
+ ASSERT_TRUE(resample_effect->set_int("width", size));
+ ASSERT_TRUE(resample_effect->set_int("height", size));
+ ASSERT_TRUE(resample_effect->set_float("left", 1.0f));
+ tester.run(out_data, GL_RED, COLORSPACE_sRGB, GAMMA_LINEAR);
+
+ expect_equal(expected_data, out_data, size, size);
+}
+
+TEST(ResampleEffectTest, ReadQuarterPixelFromLeft) {
+ const int size = 5;
+
+ float data[size * size] = {
+ 0.0, 0.0, 0.0, 0.0, 0.0,
+ 0.0, 0.0, 0.0, 0.0, 0.0,
+ 0.0, 0.0, 1.0, 0.0, 0.0,
+ 0.0, 0.0, 0.0, 0.0, 0.0,
+ 0.0, 0.0, 0.0, 0.0, 0.0,
+ };
+
+ float expected_data[size * size] = {
+ 0.0, 0.0, 0.0, 0.0, 0.0,
+ 0.0, 0.0, 0.0, 0.0, 0.0,
+
+ // sin(x*pi)/(x*pi) * sin(x*pi/3)/(x*pi/3) for
+ // x = -1.75, -0.75, 0.25, 1.25, 2.25.
+ // Note that the weight is mostly on the left side.
+ -0.06779, 0.27019, 0.89007, -0.13287, 0.03002,
+
+ 0.0, 0.0, 0.0, 0.0, 0.0,
+ 0.0, 0.0, 0.0, 0.0, 0.0,
+ };
+ float out_data[size * size];
+
+ EffectChainTester tester(data, size, size, FORMAT_GRAYSCALE, COLORSPACE_sRGB, GAMMA_LINEAR);
+ Effect *resample_effect = tester.get_chain()->add_effect(new ResampleEffect());
+ ASSERT_TRUE(resample_effect->set_int("width", size));
+ ASSERT_TRUE(resample_effect->set_int("height", size));
+ ASSERT_TRUE(resample_effect->set_float("left", 0.25f));
+ tester.run(out_data, GL_RED, COLORSPACE_sRGB, GAMMA_LINEAR);
+
+ expect_equal(expected_data, out_data, size, size);
+}
+
+TEST(ResampleEffectTest, ReadQuarterPixelFromTop) {
+ const int width = 3;
+ const int height = 5;
+
+ float data[width * height] = {
+ 0.0, 0.0, 0.0,
+ 0.0, 0.0, 0.0,
+ 1.0, 0.0, 0.0,
+ 0.0, 0.0, 0.0,
+ 0.0, 0.0, 0.0,
+ };
+
+ // See ReadQuarterPixelFromLeft for explanation of the data.
+ float expected_data[width * height] = {
+ -0.06779, 0.0, 0.0,
+ 0.27019, 0.0, 0.0,
+ 0.89007, 0.0, 0.0,
+ -0.13287, 0.0, 0.0,
+ 0.03002, 0.0, 0.0,
+ };
+ float out_data[width * height];
+
+ EffectChainTester tester(data, width, height, FORMAT_GRAYSCALE, COLORSPACE_sRGB, GAMMA_LINEAR);
+ Effect *resample_effect = tester.get_chain()->add_effect(new ResampleEffect());
+ ASSERT_TRUE(resample_effect->set_int("width", width));
+ ASSERT_TRUE(resample_effect->set_int("height", height));
+ ASSERT_TRUE(resample_effect->set_float("top", 0.25f));
+ tester.run(out_data, GL_RED, COLORSPACE_sRGB, GAMMA_LINEAR);
+
+ expect_equal(expected_data, out_data, width, height);
+}
+