Clamp viewport dimensions on store

Bug: angleproject:7486
Bug: chromium:1130759
Change-Id: I6131baacc940b5df7e33ba10fca8e6e148cb8670
Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/3751056
Reviewed-by: Kenneth Russell <kbr@chromium.org>
Reviewed-by: Shahbaz Youssefi <syoussefi@chromium.org>
Commit-Queue: Alexey Knyazev <lexa.knyazev@gmail.com>

src/libANGLE/State.cpp

@@ -1608,6 +1608,11 @@ void State::setFragmentShaderDerivativeHint(GLenum hint)
 
 void State::setViewportParams(GLint x, GLint y, GLsizei width, GLsizei height)
 {
+    // [OpenGL ES 2.0.25] section 2.12.1 page 45:
+    // Viewport width and height are clamped to implementation-dependent maximums when specified.
+    width  = std::min(width, mCaps.maxViewportWidth);
+    height = std::min(height, mCaps.maxViewportHeight);
+
     // Skip if same viewport info
     if (mViewport.x != x || mViewport.y != y || mViewport.width != width ||
         mViewport.height != height)

src/tests/gl_tests/ViewportTest.cpp

@@ -382,6 +382,56 @@ TEST_P(ViewportTest, Overflow)
     }
 }
 
+// Test that viewport dimensions are clamped to implementation-defined maximums
+TEST_P(ViewportTest, ClampOnStore)
+{
+    GLint maxDims[2];
+    glGetIntegerv(GL_MAX_VIEWPORT_DIMS, maxDims);
+    ASSERT_GT(maxDims[0], 0);
+    ASSERT_GT(maxDims[1], 0);
+
+    GLint viewport[4];
+    glViewport(0, 0, 1, 1);
+    ASSERT_GL_NO_ERROR();
+    glGetIntegerv(GL_VIEWPORT, viewport);
+    ASSERT_EQ(viewport[0], 0);
+    ASSERT_EQ(viewport[1], 0);
+    ASSERT_EQ(viewport[2], 1);
+    ASSERT_EQ(viewport[3], 1);
+
+    glViewport(0, 0, -2, 2);
+    ASSERT_GL_ERROR(GL_INVALID_VALUE);
+    glGetIntegerv(GL_VIEWPORT, viewport);
+    ASSERT_EQ(viewport[0], 0);
+    ASSERT_EQ(viewport[1], 0);
+    ASSERT_EQ(viewport[2], 1);
+    ASSERT_EQ(viewport[3], 1);
+
+    glViewport(0, 0, 3, -3);
+    ASSERT_GL_ERROR(GL_INVALID_VALUE);
+    glGetIntegerv(GL_VIEWPORT, viewport);
+    ASSERT_EQ(viewport[0], 0);
+    ASSERT_EQ(viewport[1], 0);
+    ASSERT_EQ(viewport[2], 1);
+    ASSERT_EQ(viewport[3], 1);
+
+    glViewport(0, 0, maxDims[0], maxDims[1]);
+    ASSERT_GL_NO_ERROR();
+    glGetIntegerv(GL_VIEWPORT, viewport);
+    ASSERT_EQ(viewport[0], 0);
+    ASSERT_EQ(viewport[1], 0);
+    ASSERT_EQ(viewport[2], maxDims[0]);
+    ASSERT_EQ(viewport[3], maxDims[1]);
+
+    glViewport(0, 0, maxDims[0] + 1, maxDims[1] + 1);
+    ASSERT_GL_NO_ERROR();
+    glGetIntegerv(GL_VIEWPORT, viewport);
+    ASSERT_EQ(viewport[0], 0);
+    ASSERT_EQ(viewport[1], 0);
+    ASSERT_EQ(viewport[2], maxDims[0]);
+    ASSERT_EQ(viewport[3], maxDims[1]);
+}
+
 // Use this to select which configurations (e.g. which renderer, which GLES major version) these
 // tests should be run against. D3D11 Feature Level 9 and D3D9 emulate large and negative viewports
 // in the vertex shader. We should test both of these as well as D3D11 Feature Level 10_0+.
@@ -391,6 +441,8 @@ ANGLE_INSTANTIATE_TEST(ViewportTest,
                        ES2_D3D11_PRESENT_PATH_FAST(),
                        ES2_OPENGLES(),
                        ES3_OPENGLES(),
+                       ES2_METAL(),
+                       ES2_OPENGL(),
                        ES2_VULKAN());
 
 // This test suite is not instantiated on some OSes.