Write only R channel on GL_DEPTH_COMPONENT and OpenGL ES

The affected tests fuzzily compare the results of using sized depth
textures (GL_DEPTH_COMPONENT{16,24,32}) with unsized depth texture
(GL_DEPTH_COMPONENT), which is used as reference.

According to OpenGL ES, the formers write the depth in R channel, (D,
0.0, 0.0, 1.0), while the later writes the depth in the three RGB
channels (D, D, D, 1.0).

Roughly speaking, the image in the former case is red-ish, while the
second is grayscale, and thus the comparison fails.

As only the depth is interested, just modify the test to write the red
channel in the last case.

To allow comparing them, let's just use one channel in the reference.

Components: OpenGL

VK-GL-CTS issue: 999

Affects:
KHR-GLES2.core.internalformat.texture2d.depth*
KHR-GL4*.internalformat.texture2d.depth*

Change-Id: I0bd9eea951eec0dcf91b072c476fbe0ae5292df1

diff --git a/external/openglcts/modules/common/glcInternalformatTests.cpp b/external/openglcts/modules/common/glcInternalformatTests.cpp
index f5deb48..9eb9364 100644 (file)
--- a/external/openglcts/modules/common/glcInternalformatTests.cpp
+++ b/external/openglcts/modules/common/glcInternalformatTests.cpp
@@ -351,8 +351,14 @@ glu::ProgramSources InternalformatCaseBase::prepareTexturingProgramSources(GLint
                         "varying highp vec2 texcoord;\n"
                         "void main()\n"
                         "{\n"
-                        "  gl_FragColor = texture2D(sampler, texcoord);\n"
+                        "  highp vec4 color = texture2D(sampler, texcoord);\n"
+                        "  gl_FragColor = ${CALCULATE_COLOR};\n"
                         "}\n";
+
+               if (internalFormat == GL_DEPTH_COMPONENT)
+                       specializationMap["CALCULATE_COLOR"] = "vec4(color.r, 0.0, 0.0, 1.0)";
+               else
+                       specializationMap["CALCULATE_COLOR"] = "color";
        }
 
        vs = tcu::StringTemplate(vs).specialize(specializationMap);