Implement EXT_blend_minmax.
BUG=angle:555
Change-Id: I1ae6a9783e718d16ee08bda5463f11cd52ad0967
Reviewed-on: https://chromium-review.googlesource.com/186123
Tested-by: Geoff Lang <geofflang@chromium.org>
Reviewed-by: Shannon Woods <shannonwoods@chromium.org>
diff --git a/tests/angle_tests/BlendMinMaxTest.cpp b/tests/angle_tests/BlendMinMaxTest.cpp
new file mode 100644
index 0000000..9b14fa8
--- /dev/null
+++ b/tests/angle_tests/BlendMinMaxTest.cpp
@@ -0,0 +1,155 @@
+#include "ANGLETest.h"
+
+class BlendMinMaxTest : public ANGLETest
+{
+protected:
+ BlendMinMaxTest()
+ {
+ setWindowWidth(128);
+ setWindowHeight(128);
+ setConfigRedBits(8);
+ setConfigGreenBits(8);
+ setConfigBlueBits(8);
+ setConfigAlphaBits(8);
+ setConfigDepthBits(24);
+
+ mProgram = 0;
+ mColorLocation = -1;
+ }
+
+ struct Color
+ {
+ float values[4];
+ };
+
+ static GLubyte getExpected(bool blendMin, float curColor, GLubyte prevColor)
+ {
+ GLubyte curAsUbyte = (curColor * std::numeric_limits<GLubyte>::max()) + 0.5f;
+ return blendMin ? std::min<GLubyte>(curAsUbyte, prevColor) : std::max<GLubyte>(curAsUbyte, prevColor);
+ }
+
+ void runTest()
+ {
+ const size_t colorCount = 1024;
+ Color colors[colorCount];
+ for (size_t i = 0; i < colorCount; i++)
+ {
+ for (size_t j = 0; j < 4; j++)
+ {
+ colors[i].values[j] = (rand() % 255) / 255.0f;
+ }
+ }
+
+ GLubyte prevColor[4];
+ for (size_t i = 0; i < colorCount; i++)
+ {
+ const Color &color = colors[i];
+ glUseProgram(mProgram);
+ glUniform4f(mColorLocation, color.values[0], color.values[1], color.values[2], color.values[3]);
+
+ bool blendMin = (rand() % 2 == 0);
+ glBlendEquation(blendMin ? GL_MIN : GL_MAX);
+
+ drawQuad(mProgram, "aPosition", 0.5f);
+
+ if (i > 0)
+ {
+ EXPECT_PIXEL_EQ(0, 0,
+ getExpected(blendMin, color.values[0], prevColor[0]),
+ getExpected(blendMin, color.values[1], prevColor[1]),
+ getExpected(blendMin, color.values[2], prevColor[2]),
+ getExpected(blendMin, color.values[3], prevColor[3]));
+ }
+
+ glReadPixels(0, 0, 1, 1, GL_RGBA, GL_UNSIGNED_BYTE, prevColor);
+ }
+ }
+
+ virtual void SetUp()
+ {
+ ANGLETest::SetUp();
+
+ const std::string testVertexShaderSource = SHADER_SOURCE
+ (
+ attribute highp vec4 aPosition;
+
+ void main(void)
+ {
+ gl_Position = aPosition;
+ }
+ );
+
+ const std::string testFragmentShaderSource = SHADER_SOURCE
+ (
+ uniform highp vec4 color;
+ void main(void)
+ {
+ gl_FragColor = color;
+ }
+ );
+
+ mProgram = compileProgram(testVertexShaderSource, testFragmentShaderSource);
+ if (mProgram == 0)
+ {
+ FAIL() << "shader compilation failed.";
+ }
+
+ mColorLocation = glGetUniformLocation(mProgram, "color");
+
+ glUseProgram(mProgram);
+
+ glClearColor(0, 0, 0, 0);
+ glClearDepthf(0.0);
+ glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+
+ glEnable(GL_BLEND);
+ glDisable(GL_DEPTH_TEST);
+ }
+
+ void SetUpFramebuffer(GLenum colorFormat)
+ {
+ glGenFramebuffers(1, &mFramebuffer);
+ glBindFramebuffer(GL_DRAW_FRAMEBUFFER, mFramebuffer);
+ glBindFramebuffer(GL_READ_FRAMEBUFFER, mFramebuffer);
+
+ glGenRenderbuffers(1, &mColorRenderbuffer);
+ glBindRenderbuffer(GL_RENDERBUFFER, mColorRenderbuffer);
+ glRenderbufferStorage(GL_RENDERBUFFER, colorFormat, getWindowWidth(), getWindowHeight());
+ glFramebufferRenderbuffer(GL_DRAW_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_RENDERBUFFER, mColorRenderbuffer);
+
+ ASSERT_GL_NO_ERROR();
+ }
+
+ virtual void TearDown()
+ {
+ glDeleteProgram(mProgram);
+ glDeleteFramebuffers(1, &mFramebuffer);
+ glDeleteRenderbuffers(1, &mColorRenderbuffer);
+
+ ANGLETest::TearDown();
+ }
+
+ GLuint mProgram;
+ GLint mColorLocation;
+
+ GLuint mFramebuffer;
+ GLuint mColorRenderbuffer;
+};
+
+TEST_F(BlendMinMaxTest, rgba8)
+{
+ SetUpFramebuffer(GL_RGBA8);
+ runTest();
+}
+
+TEST_F(BlendMinMaxTest, rgba32f)
+{
+ SetUpFramebuffer(GL_RGBA32F);
+ runTest();
+}
+
+TEST_F(BlendMinMaxTest, rgba16f)
+{
+ SetUpFramebuffer(GL_RGBA16F);
+ runTest();
+}