Use shader to calculate sample point
The test's sampling point is taking from interpolated varying, the inaccuracy
of interpolation may cause wrong sampling, use gl_FragCoord in fragment
shader to calcuate sample point directly.
Component: OpenGL
Affected tests: KHR-GLES32.core.nearest_edge.offset_*
VK-GL-CTS issue: 2651
Change-Id: Ib91595ca07a2b146059c51f2d68ebf086c10553c
(cherry picked from commit 3d55f6adbf38215ce3c4e2986a2a2e8a91086f08)
diff --git a/external/openglcts/modules/common/glcNearestEdgeTests.cpp b/external/openglcts/modules/common/glcNearestEdgeTests.cpp
index 621a662..f9c754a 100644
--- a/external/openglcts/modules/common/glcNearestEdgeTests.cpp
+++ b/external/openglcts/modules/common/glcNearestEdgeTests.cpp
@@ -171,32 +171,44 @@
TCU_THROW(NotSupportedError, "Render target size too small");
m_vertShaderText =
- "#version ${VERSION}\n"
- "\n"
- "in highp vec2 position;\n"
- "in highp vec2 inTexCoord;\n"
- "out highp vec2 commonTexCoord;\n"
- "\n"
- "void main()\n"
- "{\n"
- " commonTexCoord = inTexCoord;\n"
- " gl_Position = vec4(position, 0.0, 1.0);\n"
- "}\n"
- ;
-
- m_fragShaderText =
- "#version ${VERSION}\n"
- "\n"
- "in highp vec2 commonTexCoord;\n"
- "out highp vec4 fragColor;\n"
- "\n"
- "uniform highp sampler2D texSampler;\n"
- "\n"
- "void main()\n"
- "{\n"
- " fragColor = texture(texSampler, commonTexCoord);\n"
- "}\n"
- "\n";
+ "#version ${VERSION}\n"
+ "\n"
+ "in highp vec2 position;\n"
+ "\n"
+ "void main()\n"
+ "{\n"
+ " gl_Position = vec4(position, 0.0, 1.0);\n"
+ "}\n"
+ ;
+ m_fragShaderText =
+ "#version ${VERSION}\n"
+ "\n"
+ "precision highp float;\n"
+ "out highp vec4 fragColor;\n"
+ "\n"
+ "uniform highp sampler2D texSampler;\n"
+ "uniform int texOffset;\n"
+ "uniform float texWidth;\n"
+ "uniform float texHeight;\n"
+ "\n"
+ "void main()\n"
+ "{\n"
+ " float texCoordX;\n"
+ " float texCoordY;\n"
+ " if(texOffset > 0)\n"
+ " {\n"
+ " texCoordX = (gl_FragCoord.x + 0.499) / texWidth;\n "
+ " texCoordY = (gl_FragCoord.y + 0.499) / texHeight;\n"
+ " }\n"
+ " else\n"
+ " {\n"
+ " texCoordX = (gl_FragCoord.x - 0.499) / texWidth;\n"
+ " texCoordY = (gl_FragCoord.y - 0.499) / texHeight;\n"
+ " }\n"
+ " vec2 sampleCoord = vec2(texCoordX, texCoordY);\n"
+ " fragColor = texture(texSampler, sampleCoord);\n"
+ "}\n"
+ "\n";
tcu::StringTemplate vertShaderTemplate{m_vertShaderText};
tcu::StringTemplate fragShaderTemplate{m_fragShaderText};
@@ -301,8 +313,7 @@
const std::vector<glu::VertexArrayBinding> vertexArrays =
{
- glu::va::Float("position", 2, 4, 0, positions.data()),
- glu::va::Float("inTexCoord", 2, 4, 0, texCoords.data())
+ glu::va::Float("position", 2, 4, 0, positions.data())
};
glu::ShaderProgram program(m_context.getRenderContext(), glu::makeVtxFragSources(m_vertShaderText, m_fragShaderText));
@@ -315,6 +326,11 @@
gl.uniform1i(gl.getUniformLocation(program.getProgram(), "texSampler"), 0);
GLU_EXPECT_NO_ERROR(gl.getError(), "glUniform1i failed");
+ gl.uniform1i(gl.getUniformLocation(program.getProgram(), "texOffset"),m_offsetSign);
+ gl.uniform1f(gl.getUniformLocation(program.getProgram(), "texWidth"), float(m_width));
+ gl.uniform1f(gl.getUniformLocation(program.getProgram(), "texHeight"), float(m_height));
+ GLU_EXPECT_NO_ERROR(gl.getError(), "glUniform1i failed");
+
gl.clear(GL_COLOR_BUFFER_BIT);
glu::draw(renderContext, program.getProgram(),
