From d5fd8e5828846a89f826fae931775eb87b88b39b Mon Sep 17 00:00:00 2001
From: Paul Chote <pchote@users.noreply.github.com>
Date: Mon, 28 Sep 2015 18:58:36 +0100
Subject: [PATCH] Use varyings for masks instead of overloading gl_TexCoord.

---
 glsl/shp.frag |  7 +++++--
 glsl/shp.vert |  7 +++++--
 glsl/vxl.frag | 10 +++++++---
 glsl/vxl.vert | 12 ++++++++----
 4 files changed, 25 insertions(+), 11 deletions(-)

diff --git a/glsl/shp.frag b/glsl/shp.frag
index 45a3ebe467..c5671026e1 100644
--- a/glsl/shp.frag
+++ b/glsl/shp.frag
@@ -1,8 +1,11 @@
 uniform sampler2D DiffuseTexture, Palette;
 
+varying vec4 TexCoord;
+varying vec4 ChannelMask;
+
 void main()
 {
-	vec4 x = texture2D(DiffuseTexture, gl_TexCoord[0].st);
-	vec2 p = vec2(dot(x, gl_TexCoord[1]), gl_TexCoord[0].p);
+	vec4 x = texture2D(DiffuseTexture, TexCoord.st);
+	vec2 p = vec2(dot(x, ChannelMask), TexCoord.p);
 	gl_FragColor = texture2D(Palette, p);
 }
diff --git a/glsl/shp.vert b/glsl/shp.vert
index cde9c3325d..551294ffe1 100644
--- a/glsl/shp.vert
+++ b/glsl/shp.vert
@@ -1,6 +1,9 @@
 uniform vec2 Scroll;
 uniform vec2 r1,r2;		// matrix elements
 
+varying vec4 TexCoord;
+varying vec4 ChannelMask;
+
 vec4 DecodeChannelMask( float x )
 {
 	if (x > 0.0)
@@ -13,6 +16,6 @@ void main()
 {
 	vec2 p = (gl_Vertex.xy - Scroll.xy)*r1 + r2;
 	gl_Position = vec4(p.x,p.y,0,1);
-	gl_TexCoord[0] = gl_MultiTexCoord0;
-	gl_TexCoord[1] = DecodeChannelMask(gl_MultiTexCoord0.w);
+	TexCoord = gl_MultiTexCoord0;
+	ChannelMask = DecodeChannelMask(gl_MultiTexCoord0.w);
 } 
diff --git a/glsl/vxl.frag b/glsl/vxl.frag
index 492ae02fe2..c29828ea69 100644
--- a/glsl/vxl.frag
+++ b/glsl/vxl.frag
@@ -4,14 +4,18 @@ uniform vec2 PaletteRows;
 uniform vec4 LightDirection;
 uniform vec3 AmbientLight, DiffuseLight;
 
+varying vec4 TexCoord;
+varying vec4 ChannelMask;
+varying vec4 NormalsMask;
+
 void main()
 {
-	vec4 x = texture2D(DiffuseTexture, gl_TexCoord[0].st);
-	vec4 color = texture2D(Palette, vec2(dot(x, gl_TexCoord[1]), PaletteRows.x));
+	vec4 x = texture2D(DiffuseTexture, TexCoord.st);
+	vec4 color = texture2D(Palette, vec2(dot(x, ChannelMask), PaletteRows.x));
 	if (color.a < 0.01)
 		discard;
 
-	vec4 normal = (2.0 * texture2D(Palette, vec2(dot(x, gl_TexCoord[2]), PaletteRows.y)) - 1.0);
+	vec4 normal = (2.0 * texture2D(Palette, vec2(dot(x, NormalsMask), PaletteRows.y)) - 1.0);
 	vec3 intensity = AmbientLight + DiffuseLight * max(dot(normal, LightDirection), 0.0);
 	gl_FragColor = vec4(intensity * color.rgb, color.a);
 }
diff --git a/glsl/vxl.vert b/glsl/vxl.vert
index 8eb665dddb..e349fd4a2a 100644
--- a/glsl/vxl.vert
+++ b/glsl/vxl.vert
@@ -1,7 +1,11 @@
 uniform mat4 View;
 uniform mat4 TransformMatrix;
 
-vec4 DecodeChannelMask(float x)
+varying vec4 TexCoord;
+varying vec4 ChannelMask;
+varying vec4 NormalsMask;
+
+vec4 DecodeMask(float x)
 {
 	if (x > 0.0)
 		return (x > 0.5) ? vec4(1,0,0,0) : vec4(0,1,0,0);
@@ -12,7 +16,7 @@ vec4 DecodeChannelMask(float x)
 void main()
 {
 	gl_Position = View*TransformMatrix*gl_Vertex;
-	gl_TexCoord[0] = gl_MultiTexCoord0;
-	gl_TexCoord[1] = DecodeChannelMask(gl_MultiTexCoord0.z);
-	gl_TexCoord[2] = DecodeChannelMask(gl_MultiTexCoord0.w);
+	TexCoord = gl_MultiTexCoord0;
+	ChannelMask = DecodeMask(gl_MultiTexCoord0.z);
+	NormalsMask = DecodeMask(gl_MultiTexCoord0.w);
 }