From 7a9fb864ad855f43889d4f203dafe4c80acde9c6 Mon Sep 17 00:00:00 2001
From: "Jasper St. Pierre" <jstpierre@mecheye.net>
Date: Fri, 2 Jul 2021 10:36:47 -0700
Subject: [PATCH] [glsl-in] Add support for gl_FragCoord / gl_FragDepth

And remove the ability to read gl_Position in fragment.
---
 src/front/glsl/variables.rs | 19 +++++++++++++++++++
 1 file changed, 19 insertions(+)

diff --git a/src/front/glsl/variables.rs b/src/front/glsl/variables.rs
index 529036caa8..cec46cdfff 100644
--- a/src/front/glsl/variables.rs
+++ b/src/front/glsl/variables.rs
@@ -100,8 +100,27 @@ impl Program<'_> {
                 },
                 BuiltIn::Position,
                 true,
+                PrologueStage::empty(),
+            ),
+            "gl_FragCoord" => add_builtin(
+                TypeInner::Vector {
+                    size: VectorSize::Quad,
+                    kind: ScalarKind::Float,
+                    width: 4,
+                },
+                BuiltIn::Position,
+                false,
                 PrologueStage::FRAGMENT,
             ),
+            "gl_FragDepth" => add_builtin(
+                TypeInner::Scalar {
+                    kind: ScalarKind::Float,
+                    width: 4,
+                },
+                BuiltIn::FragDepth,
+                true,
+                PrologueStage::empty(),
+            ),
             "gl_VertexIndex" => add_builtin(
                 TypeInner::Scalar {
                     kind: ScalarKind::Uint,