kc3-lang/angle

2016-08-29T10:05:27

Remove invariant qualifier for input in fragment shader ESSL and GLSL are not consistent on invariant matching in vertex shader and fragment shader. See the following rules: ESSL 1.00 - input and output must match ESSL 3.00 - only output, inputs cannot be declared as invariant. GLSL 1.10.59 - does not exist GLSL 1.20.8 - input and output must match GLSL 1.30.10 - input and output must match GLSL 1.40.8 - input and output must match GLSL 1.50.11 - input and output must match GLSL 3.30.6 - input and output must match GLSL 4.00.9 - input and output must match GLSL 4.10.6 - input and output must match GLSL 4.20.11 - input can omit invariant GLSL 4.30.8 - input can omit invariant GLSL 4.40.9 - input can omit invariant GLSL 4.50.5 - input can omit invariant Since GLSL 4.20, invariant qualifier description were changed to: " Only variables output from a shader (including those that are then input to a subsequent shader) can be candidates for invariance. This includes user-defined output variables and the built-in output variables. As only outputs need be declared with invariant, an output from one shader stage will still match an input of a subsequent stage without the input being declared as invariant. " It's not very clear if input in fragment can be declared as invariant. Mesa driver disallows use of input declared as invariant in fragment shader, while other drivers may allow it. In ESSL 3.00, inputs cannot be declared as invariant. ANGLE should follow this rule for GLSL >= 4.20. BUG=chromium:639760 Change-Id: I7f7a07401381ac970488b69752f6d50d4f19d31f Reviewed-on: https://chromium-review.googlesource.com/400005 Reviewed-by: Corentin Wallez <cwallez@chromium.org> Reviewed-by: Kenneth Russell <kbr@chromium.org> Commit-Queue: Corentin Wallez <cwallez@chromium.org>