Don't rely on framebuffer contents after eglSwapBuffers

Bug 27129258

Change-Id: Ic1c58d37c665dc9c35daa2b05ca40ecb969ad5dc

diff --git a/modules/egl/teglMutableRenderBufferTests.cpp b/modules/egl/teglMutableRenderBufferTests.cpp
index 122ce5e..dfaefa1 100644 (file)
--- a/modules/egl/teglMutableRenderBufferTests.cpp
+++ b/modules/egl/teglMutableRenderBufferTests.cpp
@@ -221,35 +221,30 @@ TestCase::IterateResult MutableRenderBufferTest::iterate (void)
 
        int frameNumber = 1;
 
-       // test a few back-buffered frames
-       for(; frameNumber < 5; frameNumber++)
+       // run a few back-buffered frames even if we can't verify their contents
+       for (; frameNumber < 5; frameNumber++)
        {
-               deUint32 backBufferPixel = 0xFFFFFFFF;
-               deUint32 frontBufferPixel = drawAndSwap(egl, frameNumber, false);
-               m_gl.readPixels(0, 0, 1, 1, GL_RGBA, GL_UNSIGNED_BYTE, &backBufferPixel);
-
-               // the front-buffer and the back-buffer should have different contents
-               if (backBufferPixel == frontBufferPixel)
-               {
-                       m_testCtx.setTestResult(QP_TEST_RESULT_FAIL, "Surface isn't being back-buffered");
-                       return STOP;
-               }
+               drawAndSwap(egl, frameNumber, false);
        }
 
        // switch to single-buffer rendering
        EGLU_CHECK_CALL(egl, surfaceAttrib(m_eglDisplay, m_eglSurface, EGL_RENDER_BUFFER, EGL_SINGLE_BUFFER));
 
+       // Use eglSwapBuffers for the first frame
+       drawAndSwap(egl, frameNumber, false);
+       frameNumber++;
+
        // test a few single-buffered frames
        for (; frameNumber < 10; frameNumber++)
        {
                deUint32 backBufferPixel = 0xFFFFFFFF;
-               deUint32 frontBufferPixel = drawAndSwap(egl, frameNumber, frameNumber > 5); // only the first frame should eglSwapBuffers
+               deUint32 frontBufferPixel = drawAndSwap(egl, frameNumber, true);
                m_gl.readPixels(0, 0, 1, 1, GL_RGBA, GL_UNSIGNED_BYTE, &backBufferPixel);
 
                // when single buffered, front-buffer == back-buffer
                if (backBufferPixel != frontBufferPixel)
                {
-                       m_testCtx.setTestResult(QP_TEST_RESULT_FAIL, "Surface didn't switch to being single-buffered");
+                       m_testCtx.setTestResult(QP_TEST_RESULT_FAIL, "Surface isn't single-buffered");
                        return STOP;
                }
        }
@@ -257,19 +252,10 @@ TestCase::IterateResult MutableRenderBufferTest::iterate (void)
        // switch back to back-buffer rendering
        EGLU_CHECK_CALL(egl, surfaceAttrib(m_eglDisplay, m_eglSurface, EGL_RENDER_BUFFER, EGL_BACK_BUFFER));
 
-       // test a few back-buffered frames
-       for (; frameNumber < 15; frameNumber++)
+       // run a few back-buffered frames even if we can't verify their contents
+       for (; frameNumber < 14; frameNumber++)
        {
-               deUint32 backBufferPixel = 0xFFFFFFFF;
-               deUint32 frontBufferPixel = drawAndSwap(egl, frameNumber, false);
-               m_gl.readPixels(0, 0, 1, 1, GL_RGBA, GL_UNSIGNED_BYTE, &backBufferPixel);
-
-               // the front-buffer and the back-buffer should have different contents
-               if (backBufferPixel == frontBufferPixel)
-               {
-                       m_testCtx.setTestResult(QP_TEST_RESULT_FAIL, "Surface didn't switch back to being back-buffered");
-                       return STOP;
-               }
+               drawAndSwap(egl, frameNumber, false);
        }
 
        m_testCtx.setTestResult(QP_TEST_RESULT_PASS, "Pass");