From 71ee1a70477c5e35b4312a6c359374b7c933fc23 Mon Sep 17 00:00:00 2001
From: Robert Osfield <robert@openscenegraph.com>
Date: Sat, 17 Jan 2009 17:23:17 +0000
Subject: [PATCH] Updated Uniform name for controlling IsoSurfaceValue

---
 src/osgVolume/ShaderTechnique.cpp            | 2 ++
 src/osgVolume/Shaders/volume_iso_frag.cpp    | 7 +++----
 src/osgVolume/Shaders/volume_tf_iso_frag.cpp | 8 ++++----
 3 files changed, 9 insertions(+), 8 deletions(-)

diff --git a/src/osgVolume/ShaderTechnique.cpp b/src/osgVolume/ShaderTechnique.cpp
index a2d1564a2..7d6119abd 100644
--- a/src/osgVolume/ShaderTechnique.cpp
+++ b/src/osgVolume/ShaderTechnique.cpp
@@ -214,6 +214,8 @@ void ShaderTechnique::init()
         else if (shadingModel==Isosurface)
         {
 
+            stateset->addUniform(cpv._isoProperty->getUniform());
+
             if (tf)
             {
                 osg::Texture1D* texture1D = new osg::Texture1D;
diff --git a/src/osgVolume/Shaders/volume_iso_frag.cpp b/src/osgVolume/Shaders/volume_iso_frag.cpp
index 462910a99..120f40287 100644
--- a/src/osgVolume/Shaders/volume_iso_frag.cpp
+++ b/src/osgVolume/Shaders/volume_iso_frag.cpp
@@ -1,7 +1,7 @@
 char volume_iso_frag[] = "uniform sampler3D baseTexture;\n"
                          "uniform float sampleDensity;\n"
                          "uniform float transparency;\n"
-                         "uniform float alphaCutOff;\n"
+                         "uniform float IsoSurfaceValue;\n"
                          "\n"
                          "varying vec4 cameraPos;\n"
                          "varying vec4 vertexPos;\n"
@@ -84,10 +84,10 @@ char volume_iso_frag[] = "uniform sampler3D baseTexture;\n"
                          "    {\n"
                          "        vec4 color = texture3D( baseTexture, texcoord);\n"
                          "\n"
-                         "        float m = (previousColor.a-alphaCutOff) * (color.a-alphaCutOff);\n"
+                         "        float m = (previousColor.a-IsoSurfaceValue) * (color.a-IsoSurfaceValue);\n"
                          "        if (m <= 0.0)\n"
                          "        {\n"
-                         "            float r = (alphaCutOff-color.a)/(previousColor.a-color.a);\n"
+                         "            float r = (IsoSurfaceValue-color.a)/(previousColor.a-color.a);\n"
                          "            texcoord = texcoord - r*deltaTexCoord;\n"
                          "            \n"
                          "            float a = color.a;\n"
@@ -128,7 +128,6 @@ char volume_iso_frag[] = "uniform sampler3D baseTexture;\n"
                          "    }\n"
                          "\n"
                          "    if (fragColor.w>1.0) fragColor.w = 1.0; \n"
-                         "    //if (fragColor.w<alphaCutOff) discard;\n"
                          "    gl_FragColor = fragColor;\n"
                          "}\n"
                          "\n";
diff --git a/src/osgVolume/Shaders/volume_tf_iso_frag.cpp b/src/osgVolume/Shaders/volume_tf_iso_frag.cpp
index 2f59bf065..2ffccc6cc 100644
--- a/src/osgVolume/Shaders/volume_tf_iso_frag.cpp
+++ b/src/osgVolume/Shaders/volume_tf_iso_frag.cpp
@@ -2,7 +2,7 @@ char volume_tf_iso_frag[] = "uniform sampler3D baseTexture;\n"
                             "uniform sampler1D tfTexture;\n"
                             "uniform float sampleDensity;\n"
                             "uniform float transparency;\n"
-                            "uniform float alphaCutOff;\n"
+                            "uniform float IsoSurfaceValue;\n"
                             "\n"
                             "varying vec4 cameraPos;\n"
                             "varying vec4 vertexPos;\n"
@@ -84,10 +84,10 @@ char volume_tf_iso_frag[] = "uniform sampler3D baseTexture;\n"
                             "\n"
                             "        float v = texture3D( baseTexture, texcoord).a;\n"
                             "\n"
-                            "        float m = (previousV-alphaCutOff) * (v-alphaCutOff);\n"
+                            "        float m = (previousV-IsoSurfaceValue) * (v-IsoSurfaceValue);\n"
                             "        if (m <= 0.0)\n"
                             "        {\n"
-                            "            float r = (alphaCutOff-v)/(previousV-v);\n"
+                            "            float r = (IsoSurfaceValue-v)/(previousV-v);\n"
                             "            texcoord = texcoord - r*deltaTexCoord;\n"
                             "\n"
                             "            v = texture3D( baseTexture, texcoord).a;\n"
@@ -123,7 +123,7 @@ char volume_tf_iso_frag[] = "uniform sampler3D baseTexture;\n"
                             "    }\n"
                             "\n"
                             "    if (fragColor.w>1.0) fragColor.w = 1.0; \n"
-                            "    if (fragColor.w<alphaCutOff) discard;\n"
+                            "    if (fragColor.w<IsoSurfaceValue) discard;\n"
                             "    gl_FragColor = fragColor;\n"
                             "}\n"
                             "\n";