+// Unit tests for GlowEffect.
+
+#include <math.h>
+
+#include "test_util.h"
+#include "gtest/gtest.h"
+#include "glow_effect.h"
+
+TEST(GlowEffectTest, NoAmountDoesNothing) {
+ const int size = 4;
+
+ float data[size * size] = {
+ 0.0, 1.0, 0.0, 1.0,
+ 0.0, 1.0, 1.0, 0.0,
+ 0.0, 0.5, 1.0, 0.5,
+ 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 *glow_effect = tester.get_chain()->add_effect(new GlowEffect());
+ ASSERT_TRUE(glow_effect->set_float("radius", 2.0f));
+ ASSERT_TRUE(glow_effect->set_float("blurred_mix_amount", 0.0f));
+ tester.run(out_data, GL_RED, COLORSPACE_sRGB, GAMMA_LINEAR);
+
+ expect_equal(data, out_data, size, size);
+}
+
+TEST(GlowEffectTest, SingleDot) {
+ const int size = 13;
+ const float sigma = 0.5f;
+ const float amount = 0.2f;
+
+ float data[] = { // One single dot in the middle.
+ 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,
+ 0.0, 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, 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, 0.0, 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, 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, 0.0, 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, 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, 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, 0.0, 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, 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, 0.0, 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, 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, 0.0, 0.0, 0.0, 0.0,
+ };
+ float expected_data[size * size], out_data[size * size];
+
+ // The output should be equal to the input, plus approximately a logistic blob.
+ // From http://en.wikipedia.org/wiki/Logistic_distribution#Alternative_parameterization.
+ const float c1 = M_PI / (sigma * 4 * sqrt(3.0f));
+ const float c2 = M_PI / (sigma * 2.0 * sqrt(3.0f));
+
+ for (int y = 0; y < size; ++y) {
+ for (int x = 0; x < size; ++x) {
+ float xd = c2 * (x - 6);
+ float yd = c2 * (y - 6);
+ expected_data[y * size + x] = data[y * size + x] +
+ (amount * c1 * c1) / (cosh(xd) * cosh(xd) * cosh(yd) * cosh(yd));
+ }
+ }
+
+ EffectChainTester tester(data, size, size, FORMAT_GRAYSCALE, COLORSPACE_sRGB, GAMMA_LINEAR);
+ Effect *glow_effect = tester.get_chain()->add_effect(new GlowEffect());
+ ASSERT_TRUE(glow_effect->set_float("radius", sigma));
+ ASSERT_TRUE(glow_effect->set_float("blurred_mix_amount", amount));
+ tester.run(out_data, GL_RED, COLORSPACE_sRGB, GAMMA_LINEAR);
+
+ expect_equal(expected_data, out_data, size, size, 0.1f, 1e-3);
+}
+
+TEST(GlowEffectTest, GlowsOntoZeroAlpha) {
+ const int size = 7;
+ const float sigma = 1.0f;
+ const float amount = 1.0f;
+
+ float data[4 * 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,
+ 0.0, 1.0, 0.0, 0.5,
+ 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[4 * size] = {
+ 0.0, 1.0, 0.0, 0.002,
+ 0.0, 1.0, 0.0, 0.014,
+ 0.0, 1.0, 0.0, 0.065,
+ 0.0, 1.0, 0.0, 0.635,
+ 0.0, 1.0, 0.0, 0.065,
+ 0.0, 1.0, 0.0, 0.014,
+ 0.0, 1.0, 0.0, 0.002,
+ };
+
+ float out_data[4 * size];
+
+ EffectChainTester tester(data, 1, size, FORMAT_RGBA_POSTMULTIPLIED_ALPHA, COLORSPACE_sRGB, GAMMA_LINEAR);
+ Effect *glow_effect = tester.get_chain()->add_effect(new GlowEffect());
+ ASSERT_TRUE(glow_effect->set_float("radius", sigma));
+ ASSERT_TRUE(glow_effect->set_float("blurred_mix_amount", amount));
+ tester.run(out_data, GL_RGBA, COLORSPACE_sRGB, GAMMA_LINEAR);
+
+ expect_equal(expected_data, out_data, 4, size);
+}