From 4734c5b64ac423766702881753c41a8cc09da65f Mon Sep 17 00:00:00 2001
From: Bill Currie <bill@taniwha.org>
Date: Sat, 28 Jan 2012 21:20:34 +0900
Subject: [PATCH] Implement water alpha.

---
 libs/video/renderer/glsl/glsl_bsp.c    | 16 ++++++++++++++++
 libs/video/renderer/glsl/quakebsp.frag |  3 ++-
 libs/video/renderer/glsl/quakebsp.vert |  3 +++
 libs/video/renderer/glsl/quaketrb.frag |  3 ++-
 4 files changed, 23 insertions(+), 2 deletions(-)

diff --git a/libs/video/renderer/glsl/glsl_bsp.c b/libs/video/renderer/glsl/glsl_bsp.c
index a53847ed1..8d9c22baa 100644
--- a/libs/video/renderer/glsl/glsl_bsp.c
+++ b/libs/video/renderer/glsl/glsl_bsp.c
@@ -132,6 +132,7 @@ static struct {
 	shaderparam_t colormap;
 	shaderparam_t texture;
 	shaderparam_t lightmap;
+	shaderparam_t color;
 } quake_bsp = {
 	0,
 	{"mvp_mat", 1},
@@ -140,6 +141,7 @@ static struct {
 	{"colormap", 1},
 	{"texture", 1},
 	{"lightmap", 1},
+	{"vcolor", 0},
 };
 
 static struct {
@@ -150,6 +152,7 @@ static struct {
 	shaderparam_t palette;
 	shaderparam_t texture;
 	shaderparam_t realtime;
+	shaderparam_t color;
 } quake_turb = {
 	0,
 	{"mvp_mat", 1},
@@ -158,6 +161,7 @@ static struct {
 	{"palette", 1},
 	{"texture", 1},
 	{"realtime", 1},
+	{"vcolor", 0},
 };
 
 static struct {
@@ -800,11 +804,15 @@ draw_elechain (elechain_t *ec, int matloc, int vertloc, int tlstloc)
 static void
 bsp_begin (void)
 {
+	static quat_t color = { 1, 1, 1, 1 };
 	Mat4Mult (glsl_projection, glsl_view, bsp_vp);
 
 	qfglUseProgram (quake_bsp.program);
 	qfglEnableVertexAttribArray (quake_bsp.vertex.location);
 	qfglEnableVertexAttribArray (quake_bsp.tlst.location);
+	qfglDisableVertexAttribArray (quake_bsp.color.location);
+
+	qfglVertexAttrib4fv (quake_bsp.color.location, color);
 
 	qfglUniform1i (quake_bsp.colormap.location, 2);
 	qfglActiveTexture (GL_TEXTURE0 + 2);
@@ -842,11 +850,17 @@ bsp_end (void)
 static void
 turb_begin (void)
 {
+	static quat_t color = { 1, 1, 1, 1 };
+
 	Mat4Mult (glsl_projection, glsl_view, bsp_vp);
 
 	qfglUseProgram (quake_turb.program);
 	qfglEnableVertexAttribArray (quake_turb.vertex.location);
 	qfglEnableVertexAttribArray (quake_turb.tlst.location);
+	qfglDisableVertexAttribArray (quake_bsp.color.location);
+
+	color[3] = bound (0, r_wateralpha->value, 1);
+	qfglVertexAttrib4fv (quake_turb.color.location, color);
 
 	qfglUniform1i (quake_turb.palette.location, 1);
 	qfglActiveTexture (GL_TEXTURE0 + 1);
@@ -1168,6 +1182,7 @@ R_InitBsp (void)
 	GL_ResolveShaderParam (quake_bsp.program, &quake_bsp.colormap);
 	GL_ResolveShaderParam (quake_bsp.program, &quake_bsp.texture);
 	GL_ResolveShaderParam (quake_bsp.program, &quake_bsp.lightmap);
+	GL_ResolveShaderParam (quake_bsp.program, &quake_bsp.color);
 
 	frag = GL_CompileShader ("quaketrb.frag", quaketurb_frag,
 							 GL_FRAGMENT_SHADER);
@@ -1178,6 +1193,7 @@ R_InitBsp (void)
 	GL_ResolveShaderParam (quake_turb.program, &quake_turb.palette);
 	GL_ResolveShaderParam (quake_turb.program, &quake_turb.texture);
 	GL_ResolveShaderParam (quake_turb.program, &quake_turb.realtime);
+	GL_ResolveShaderParam (quake_turb.program, &quake_turb.color);
 
 	vert = GL_CompileShader ("quakesky.vert", quakesky_vert, GL_VERTEX_SHADER);
 	frag = GL_CompileShader ("quakeski.frag", quakeskyid_frag,
diff --git a/libs/video/renderer/glsl/quakebsp.frag b/libs/video/renderer/glsl/quakebsp.frag
index 162461309..bfdb24fbb 100644
--- a/libs/video/renderer/glsl/quakebsp.frag
+++ b/libs/video/renderer/glsl/quakebsp.frag
@@ -4,6 +4,7 @@ uniform sampler2D lightmap;
 
 varying vec2 tst;
 varying vec2 lst;
+varying vec4 color;
 
 void
 main (void)
@@ -12,5 +13,5 @@ main (void)
 	float       light = texture2D (lightmap, lst).r;
 	float       col;
 
-	gl_FragColor = texture2D (colormap, vec2 (pix, light * 4.0));
+	gl_FragColor = texture2D (colormap, vec2 (pix, light * 4.0)) * color;
 }
diff --git a/libs/video/renderer/glsl/quakebsp.vert b/libs/video/renderer/glsl/quakebsp.vert
index 8992ac37e..fc22d17e6 100644
--- a/libs/video/renderer/glsl/quakebsp.vert
+++ b/libs/video/renderer/glsl/quakebsp.vert
@@ -1,10 +1,12 @@
 uniform mat4 mvp_mat;
 
+attribute vec4 vcolor;
 attribute vec4 tlst;
 attribute vec4 vertex;
 
 varying vec2 tst;
 varying vec2 lst;
+varying vec4 color;
 
 void
 main (void)
@@ -12,4 +14,5 @@ main (void)
 	gl_Position = mvp_mat * vertex;
 	tst = tlst.st;
 	lst = tlst.pq;
+	color = vcolor;
 }
diff --git a/libs/video/renderer/glsl/quaketrb.frag b/libs/video/renderer/glsl/quaketrb.frag
index 7828cab87..cc3f13e0a 100644
--- a/libs/video/renderer/glsl/quaketrb.frag
+++ b/libs/video/renderer/glsl/quaketrb.frag
@@ -3,6 +3,7 @@ uniform sampler2D texture;
 uniform float realtime;
 
 varying vec2 tst;
+varying vec4 color;
 
 const float SPEED = 20.0;
 const float CYCLE = 128.0;
@@ -27,5 +28,5 @@ main (void)
 
 	st = turb_st (tst, realtime);
 	pix = texture2D (texture, st).r;
-	gl_FragColor = texture2D (palette, vec2 (pix, 0.0));
+	gl_FragColor = texture2D (palette, vec2 (pix, 0.0)) * color;
 }