From 7b4d66b621f28cedb47fd8400a6d8fcb75c22b86 Mon Sep 17 00:00:00 2001
From: Anthony Ramine <n.oxyde@gmail.com>
Date: Wed, 4 Apr 2018 16:22:28 +0200
Subject: [PATCH] Manually clamp the argument of
 WebGLRenderingContext.clearDepth

Better be safe than to feed stuff to some GPU driver that wouldn't clamp it.
---
 components/canvas/webgl_thread.rs              | 5 +++--
 components/canvas_traits/webgl.rs              | 2 +-
 components/script/dom/webglrenderingcontext.rs | 2 +-
 3 files changed, 5 insertions(+), 4 deletions(-)

diff --git a/components/canvas/webgl_thread.rs b/components/canvas/webgl_thread.rs
index 933c8893cf2..01ab0a15250 100644
--- a/components/canvas/webgl_thread.rs
+++ b/components/canvas/webgl_thread.rs
@@ -678,8 +678,9 @@ impl WebGLImpl {
                 ctx.gl().clear(mask),
             WebGLCommand::ClearColor(r, g, b, a) =>
                 ctx.gl().clear_color(r, g, b, a),
-            WebGLCommand::ClearDepth(depth) =>
-                ctx.gl().clear_depth(depth),
+            WebGLCommand::ClearDepth(depth) => {
+                ctx.gl().clear_depth(depth.max(0.).min(1.) as f64)
+            }
             WebGLCommand::ClearStencil(stencil) =>
                 ctx.gl().clear_stencil(stencil),
             WebGLCommand::ColorMask(r, g, b, a) =>
diff --git a/components/canvas_traits/webgl.rs b/components/canvas_traits/webgl.rs
index 55d2843c276..01e3c49fc3d 100644
--- a/components/canvas_traits/webgl.rs
+++ b/components/canvas_traits/webgl.rs
@@ -170,7 +170,7 @@ pub enum WebGLCommand {
     BufferSubData(u32, isize, ByteBuf),
     Clear(u32),
     ClearColor(f32, f32, f32, f32),
-    ClearDepth(f64),
+    ClearDepth(f32),
     ClearStencil(i32),
     ColorMask(bool, bool, bool, bool),
     CullFace(u32),
diff --git a/components/script/dom/webglrenderingcontext.rs b/components/script/dom/webglrenderingcontext.rs
index 5819b33357e..81f28ceb1cd 100644
--- a/components/script/dom/webglrenderingcontext.rs
+++ b/components/script/dom/webglrenderingcontext.rs
@@ -1876,7 +1876,7 @@ impl WebGLRenderingContextMethods for WebGLRenderingContext {
 
     // https://www.khronos.org/registry/webgl/specs/latest/1.0/#5.14.3
     fn ClearDepth(&self, depth: f32) {
-        self.send_command(WebGLCommand::ClearDepth(depth as f64))
+        self.send_command(WebGLCommand::ClearDepth(depth))
     }
 
     // https://www.khronos.org/registry/webgl/specs/latest/1.0/#5.14.3