Fix the condition of glOrtho{fx} validation

src/libANGLE/validationES1.cpp

@@ -1123,7 +1123,10 @@ bool ValidateOrthof(const Context *context,
                     GLfloat f)
 {
     ANGLE_VALIDATE_IS_GLES1(context);
-    if (l == r || b == t || n == f || n <= 0.0f || f <= 0.0f)
+    // [OpenGL ES 1.1.12] section 2.10.2 page 31:
+    // If l is equal to r, b is equal to t, or n is equal to f, the
+    // error INVALID VALUE results.
+    if (l == r || b == t || n == f)
     {
         context->validationError(GL_INVALID_VALUE, kInvalidProjectionMatrix);
     }
@@ -1139,7 +1142,7 @@ bool ValidateOrthox(const Context *context,
                     GLfixed f)
 {
     ANGLE_VALIDATE_IS_GLES1(context);
-    if (l == r || b == t || n == f || n <= 0 || f <= 0)
+    if (l == r || b == t || n == f)
     {
         context->validationError(GL_INVALID_VALUE, kInvalidProjectionMatrix);
     }

src/tests/gl_tests/gles1/MatrixBuiltinsTest.cpp

@@ -165,12 +165,19 @@ TEST_P(MatrixBuiltinsTest, OrthoNegative)
     EXPECT_GL_ERROR(GL_INVALID_VALUE);
     glOrthof(0.0f, 1.0f, 0.0f, 1.0f, 1.0f, 1.0f);
     EXPECT_GL_ERROR(GL_INVALID_VALUE);
-    glOrthof(0.0f, 1.0f, 0.0f, 1.0f, 0.0f, 1.0f);
-    EXPECT_GL_ERROR(GL_INVALID_VALUE);
-    glOrthof(0.0f, 1.0f, 0.0f, 1.0f, 1.0f, 0.0f);
-    EXPECT_GL_ERROR(GL_INVALID_VALUE);
-    glOrthof(0.0f, 1.0f, 0.0f, 1.0f, -1.0f, 1.0f);
-    EXPECT_GL_ERROR(GL_INVALID_VALUE);
+}
+
+// Test that glOrtho{fx} don't issue error result if near or far is negative.
+TEST_P(MatrixBuiltinsTest, OrthoNegativeNearFar)
+{
+    glOrthof(-1.0f, 1.0f, -1.0f, 1.0f, -1.0f, 0.0f);
+    EXPECT_GL_NO_ERROR();
+    glOrthof(-1.0f, 1.0f, -1.0f, 1.0f, 0.0f, -1.0f);
+    EXPECT_GL_NO_ERROR();
+    glOrthox(-1, 1, -1, 1, -1, 0);
+    EXPECT_GL_NO_ERROR();
+    glOrthox(-1, 1, -1, 1, 0, -1);
+    EXPECT_GL_NO_ERROR();
 }
 
 ANGLE_INSTANTIATE_TEST_ES1(MatrixBuiltinsTest);