Add terrain shaders and normal map support

Textures with _n filename suffix are automatically recognized as terrain normal maps.

components/resource/scenemanager.cpp

@@ -228,6 +228,11 @@ namespace Resource
         mForceShaders = force;
     }
 
+    bool SceneManager::getForceShaders() const
+    {
+        return mForceShaders;
+    }
+
     void SceneManager::recreateShaders(osg::ref_ptr<osg::Node> node)
     {
         Shader::ShaderVisitor shaderVisitor(*mShaderManager.get(), "objects_vertex.glsl", "objects_fragment.glsl");
@@ -243,16 +248,31 @@ namespace Resource
         mClampLighting = clamp;
     }
 
+    bool SceneManager::getClampLighting() const
+    {
+        return mClampLighting;
+    }
+
     void SceneManager::setForcePerPixelLighting(bool force)
     {
         mForcePerPixelLighting = force;
     }
 
+    bool SceneManager::getForcePerPixelLighting() const
+    {
+        return mForcePerPixelLighting;
+    }
+
     SceneManager::~SceneManager()
     {
         // this has to be defined in the .cpp file as we can't delete incomplete types
     }
 
+    Shader::ShaderManager &SceneManager::getShaderManager()
+    {
+        return *mShaderManager.get();
+    }
+
     void SceneManager::setShaderPath(const std::string &path)
     {
         mShaderManager->setShaderPath(path);

components/resource/scenemanager.hpp

@@ -40,17 +40,22 @@ namespace Resource
         SceneManager(const VFS::Manager* vfs, Resource::ImageManager* imageManager, Resource::NifFileManager* nifFileManager);
         ~SceneManager();
 
+        Shader::ShaderManager& getShaderManager();
+
         /// Re-create shaders for this node, need to call this if texture stages or vertex color mode have changed.
         void recreateShaders(osg::ref_ptr<osg::Node> node);
 
         /// @see ShaderVisitor::setForceShaders
         void setForceShaders(bool force);
+        bool getForceShaders() const;
 
         /// @see ShaderVisitor::setClampLighting
         void setClampLighting(bool clamp);
+        bool getClampLighting() const;
 
         /// @see ShaderVisitor::setForcePerPixelLighting
         void setForcePerPixelLighting(bool force);
+        bool getForcePerPixelLighting() const;
 
         void setShaderPath(const std::string& path);
 

components/terrain/material.cpp

@@ -1,21 +1,26 @@
 #include "material.hpp"
 
+#include <iostream>
+#include <stdexcept>
+
 #include <osg/Depth>
 #include <osg/TexEnvCombine>
 #include <osg/Texture2D>
 #include <osg/TexMat>
 #include <osg/Material>
-#include <osg/TexEnvCombine>
+
+#include <components/shader/shadermanager.hpp>
+
 
 namespace Terrain
 {
 
-    FixedFunctionTechnique::FixedFunctionTechnique(const std::vector<osg::ref_ptr<osg::Texture2D> >& layers,
+    FixedFunctionTechnique::FixedFunctionTechnique(const std::vector<TextureLayer>& layers,
                                                    const std::vector<osg::ref_ptr<osg::Texture2D> >& blendmaps, int blendmapScale, float layerTileSize)
     {
         bool firstLayer = true;
         int i=0;
-        for (std::vector<osg::ref_ptr<osg::Texture2D> >::const_iterator it = layers.begin(); it != layers.end(); ++it)
+        for (std::vector<TextureLayer>::const_iterator it = layers.begin(); it != layers.end(); ++it)
         {
             osg::ref_ptr<osg::StateSet> stateset (new osg::StateSet);
 
@@ -53,7 +58,7 @@ namespace Terrain
             }
 
             // Add the actual layer texture multiplied by the alpha map.
-            osg::ref_ptr<osg::Texture2D> tex = *it;
+            osg::ref_ptr<osg::Texture2D> tex = it->mDiffuseMap;
             stateset->setTextureAttributeAndModes(texunit, tex.get());
 
             osg::ref_ptr<osg::TexMat> texMat (new osg::TexMat);
@@ -66,9 +71,85 @@ namespace Terrain
         }
     }
 
-    Effect::Effect(const std::vector<osg::ref_ptr<osg::Texture2D> > &layers, const std::vector<osg::ref_ptr<osg::Texture2D> > &blendmaps,
+    ShaderTechnique::ShaderTechnique(Shader::ShaderManager& shaderManager, bool forcePerPixelLighting, bool clampLighting, const std::vector<TextureLayer>& layers,
+                                                   const std::vector<osg::ref_ptr<osg::Texture2D> >& blendmaps, int blendmapScale, float layerTileSize)
+    {
+        bool firstLayer = true;
+        int i=0;
+        for (std::vector<TextureLayer>::const_iterator it = layers.begin(); it != layers.end(); ++it)
+        {
+            osg::ref_ptr<osg::StateSet> stateset (new osg::StateSet);
+
+            if (!firstLayer)
+            {
+                stateset->setMode(GL_BLEND, osg::StateAttribute::ON);
+                osg::ref_ptr<osg::Depth> depth (new osg::Depth);
+                depth->setFunction(osg::Depth::EQUAL);
+                stateset->setAttributeAndModes(depth, osg::StateAttribute::ON);
+            }
+
+            int texunit = 0;
+
+            stateset->setTextureAttributeAndModes(texunit, it->mDiffuseMap);
+
+            osg::ref_ptr<osg::TexMat> texMat (new osg::TexMat);
+            texMat->setMatrix(osg::Matrix::scale(osg::Vec3f(layerTileSize,layerTileSize,1.f)));
+            stateset->setTextureAttributeAndModes(texunit, texMat, osg::StateAttribute::ON);
+
+            stateset->addUniform(new osg::Uniform("diffuseMap", texunit));
+
+            if(!firstLayer)
+            {
+                ++texunit;
+                osg::ref_ptr<osg::Texture2D> blendmap = blendmaps.at(i++);
+
+                stateset->setTextureAttributeAndModes(texunit, blendmap.get());
+
+                // This is to map corner vertices directly to the center of a blendmap texel.
+                osg::Matrixf texMat;
+                float scale = (blendmapScale/(static_cast<float>(blendmapScale)+1.f));
+                texMat.preMultTranslate(osg::Vec3f(0.5f, 0.5f, 0.f));
+                texMat.preMultScale(osg::Vec3f(scale, scale, 1.f));
+                texMat.preMultTranslate(osg::Vec3f(-0.5f, -0.5f, 0.f));
+
+                stateset->setTextureAttributeAndModes(texunit, new osg::TexMat(texMat));
+                stateset->addUniform(new osg::Uniform("blendMap", texunit));
+            }
+
+            if (it->mNormalMap)
+            {
+                ++texunit;
+                stateset->setTextureAttributeAndModes(texunit, it->mNormalMap);
+                stateset->addUniform(new osg::Uniform("normalMap", texunit));
+            }
+
+            Shader::ShaderManager::DefineMap defineMap;
+            defineMap["forcePPL"] = forcePerPixelLighting ? "1" : "0";
+            defineMap["clamp"] = clampLighting ? "1" : "0";
+            defineMap["normalMap"] = (it->mNormalMap) ? "1" : "0";
+            defineMap["blendMap"] = !firstLayer ? "1" : "0";
+            defineMap["colorMode"] = "2";
+
+            osg::ref_ptr<osg::Shader> vertexShader = shaderManager.getShader("terrain_vertex.glsl", defineMap, osg::Shader::VERTEX);
+            osg::ref_ptr<osg::Shader> fragmentShader = shaderManager.getShader("terrain_fragment.glsl", defineMap, osg::Shader::FRAGMENT);
+            if (!vertexShader || !fragmentShader)
+                throw std::runtime_error("Unable to create shader");
+
+            stateset->setAttributeAndModes(shaderManager.getProgram(vertexShader, fragmentShader));
+
+            firstLayer = false;
+
+            addPass(stateset);
+        }
+    }
+
+    Effect::Effect(bool useShaders, bool forcePerPixelLighting, bool clampLighting, Shader::ShaderManager& shaderManager, const std::vector<TextureLayer> &layers, const std::vector<osg::ref_ptr<osg::Texture2D> > &blendmaps,
                    int blendmapScale, float layerTileSize)
-        : mLayers(layers)
+        : mShaderManager(shaderManager)
+        , mUseShaders(useShaders)
+        , mForcePerPixelLighting(forcePerPixelLighting)
+        , mClampLighting(clampLighting)
+        , mLayers(layers)
         , mBlendmaps(blendmaps)
         , mBlendmapScale(blendmapScale)
         , mLayerTileSize(layerTileSize)
@@ -82,7 +163,18 @@ namespace Terrain
 
     bool Effect::define_techniques()
     {
-        addTechnique(new FixedFunctionTechnique(mLayers, mBlendmaps, mBlendmapScale, mLayerTileSize));
+        try
+        {
+            if (mUseShaders)
+                addTechnique(new ShaderTechnique(mShaderManager, mForcePerPixelLighting, mClampLighting, mLayers, mBlendmaps, mBlendmapScale, mLayerTileSize));
+            else
+                addTechnique(new FixedFunctionTechnique(mLayers, mBlendmaps, mBlendmapScale, mLayerTileSize));
+        }
+        catch (std::exception& e)
+        {
+            std::cerr << "Error: " << e.what() << std::endl;
+            addTechnique(new FixedFunctionTechnique(mLayers, mBlendmaps, mBlendmapScale, mLayerTileSize));
+        }
 
         return true;
     }

components/terrain/material.hpp

@@ -11,14 +11,36 @@ namespace osg
     class Texture2D;
 }
 
+namespace Shader
+{
+    class ShaderManager;
+}
+
 namespace Terrain
 {
 
+    struct TextureLayer
+    {
+        osg::ref_ptr<osg::Texture2D> mDiffuseMap;
+        osg::ref_ptr<osg::Texture2D> mNormalMap; // optional
+    };
+
     class FixedFunctionTechnique : public osgFX::Technique
     {
     public:
         FixedFunctionTechnique(
-                const std::vector<osg::ref_ptr<osg::Texture2D> >& layers,
+                const std::vector<TextureLayer>& layers,
+                const std::vector<osg::ref_ptr<osg::Texture2D> >& blendmaps, int blendmapScale, float layerTileSize);
+
+    protected:
+        virtual void define_passes() {}
+    };
+
+    class ShaderTechnique : public osgFX::Technique
+    {
+    public:
+        ShaderTechnique(Shader::ShaderManager& shaderManager, bool forcePerPixelLighting, bool clampLighting,
+                const std::vector<TextureLayer>& layers,
                 const std::vector<osg::ref_ptr<osg::Texture2D> >& blendmaps, int blendmapScale, float layerTileSize);
 
     protected:
@@ -28,8 +50,8 @@ namespace Terrain
     class Effect : public osgFX::Effect
     {
     public:
-        Effect(
-                const std::vector<osg::ref_ptr<osg::Texture2D> >& layers,
+        Effect(bool useShaders, bool forcePerPixelLighting, bool clampLighting, Shader::ShaderManager& shaderManager,
+                const std::vector<TextureLayer>& layers,
                 const std::vector<osg::ref_ptr<osg::Texture2D> >& blendmaps, int blendmapScale, float layerTileSize);
 
         virtual bool define_techniques();
@@ -48,7 +70,11 @@ namespace Terrain
         }
 
     private:
-        std::vector<osg::ref_ptr<osg::Texture2D> > mLayers;
+        Shader::ShaderManager& mShaderManager;
+        bool mUseShaders;
+        bool mForcePerPixelLighting;
+        bool mClampLighting;
+        std::vector<TextureLayer> mLayers;
         std::vector<osg::ref_ptr<osg::Texture2D> > mBlendmaps;
         int mBlendmapScale;
         float mLayerTileSize;

components/terrain/terraingrid.cpp

@@ -148,11 +148,15 @@ osg::ref_ptr<osg::Node> TerrainGrid::buildTerrain (osg::Group* parent, float chu
         osg::ref_ptr<osg::Node> textureCompileDummy (new osg::Node);
         unsigned int dummyTextureCounter = 0;
 
-        std::vector<osg::ref_ptr<osg::Texture2D> > layerTextures;
+        bool useShaders = mResourceSystem->getSceneManager()->getForceShaders();
+        if (!mResourceSystem->getSceneManager()->getClampLighting())
+            useShaders = true; // always use shaders when lighting is unclamped, this is to avoid lighting seams between a terrain chunk with normal maps and one without normal maps
+        std::vector<TextureLayer> layers;
         {
             OpenThreads::ScopedLock<OpenThreads::Mutex> lock(mTextureCacheMutex);
             for (std::vector<LayerInfo>::const_iterator it = layerList.begin(); it != layerList.end(); ++it)
             {
+                TextureLayer textureLayer;
                 osg::ref_ptr<osg::Texture2D> texture = mTextureCache[it->mDiffuseMap];
                 if (!texture)
                 {
@@ -162,8 +166,26 @@ osg::ref_ptr<osg::Node> TerrainGrid::buildTerrain (osg::Group* parent, float chu
                     mResourceSystem->getSceneManager()->applyFilterSettings(texture);
                     mTextureCache[it->mDiffuseMap] = texture;
                 }
-                layerTextures.push_back(texture);
-                textureCompileDummy->getOrCreateStateSet()->setTextureAttributeAndModes(dummyTextureCounter++, layerTextures.back());
+                textureLayer.mDiffuseMap = texture;
+                textureCompileDummy->getOrCreateStateSet()->setTextureAttributeAndModes(dummyTextureCounter++, texture);
+
+                if (!it->mNormalMap.empty())
+                {
+                    texture = mTextureCache[it->mNormalMap];
+                    if (!texture)
+                    {
+                        texture = new osg::Texture2D(mResourceSystem->getImageManager()->getImage(it->mNormalMap));
+                        texture->setWrap(osg::Texture::WRAP_S, osg::Texture::REPEAT);
+                        texture->setWrap(osg::Texture::WRAP_T, osg::Texture::REPEAT);
+                        mResourceSystem->getSceneManager()->applyFilterSettings(texture);
+                        mTextureCache[it->mNormalMap] = texture;
+                    }
+                    textureCompileDummy->getOrCreateStateSet()->setTextureAttributeAndModes(dummyTextureCounter++, texture);
+                    textureLayer.mNormalMap = texture;
+                    useShaders = true;
+                }
+
+                layers.push_back(textureLayer);
             }
         }
 
@@ -185,7 +207,8 @@ osg::ref_ptr<osg::Node> TerrainGrid::buildTerrain (osg::Group* parent, float chu
             geometry->setTexCoordArray(i, mCache.getUVBuffer());
 
         float blendmapScale = ESM::Land::LAND_TEXTURE_SIZE*chunkSize;
-        osg::ref_ptr<osgFX::Effect> effect (new Terrain::Effect(layerTextures, blendmapTextures, blendmapScale, blendmapScale));
+        osg::ref_ptr<osgFX::Effect> effect (new Terrain::Effect(useShaders, mResourceSystem->getSceneManager()->getForcePerPixelLighting(), mResourceSystem->getSceneManager()->getClampLighting(),
+                                                                mResourceSystem->getSceneManager()->getShaderManager(), layers, blendmapTextures, blendmapScale, blendmapScale));
 
         effect->addCullCallback(new SceneUtil::LightListCallback);
 

files/shaders/CMakeLists.txt

@@ -8,6 +8,8 @@ set(SHADER_FILES
     water_nm.png
     objects_vertex.glsl
     objects_fragment.glsl
+    terrain_vertex.glsl
+    terrain_fragment.glsl
     lighting.glsl
 )
 

files/shaders/terrain_fragment.glsl

@@ -0,0 +1,64 @@
+#version 120
+
+varying vec2 uv;
+
+uniform sampler2D diffuseMap;
+
+#if @normalMap
+uniform sampler2D normalMap;
+#endif
+
+#if @blendMap
+uniform sampler2D blendMap;
+#endif
+
+varying float depth;
+
+#define PER_PIXEL_LIGHTING (@normalMap || @forcePPL)
+
+#if !PER_PIXEL_LIGHTING
+varying vec4 lighting;
+#else
+varying vec3 passViewPos;
+varying vec3 passViewNormal;
+varying vec4 passColor;
+#endif
+
+#include "lighting.glsl"
+
+void main()
+{
+    vec2 diffuseMapUV = (gl_TextureMatrix[0] * vec4(uv, 0.0, 1.0)).xy;
+
+    gl_FragData[0] = vec4(texture2D(diffuseMap, diffuseMapUV).xyz, 1.0);
+
+#if @blendMap
+    vec2 blendMapUV = (gl_TextureMatrix[1] * vec4(uv, 0.0, 1.0)).xy;
+    gl_FragData[0].a *= texture2D(blendMap, blendMapUV).a;
+#endif
+
+#if PER_PIXEL_LIGHTING
+    vec3 viewNormal = passViewNormal;
+#endif
+
+#if @normalMap
+    vec3 normalTex = texture2D(normalMap, diffuseMapUV).xyz;
+
+    vec3 viewTangent = (gl_ModelViewMatrix * vec4(1.0, 0.0, 0.0, 0.0)).xyz;
+    vec3 viewBinormal = normalize(cross(viewTangent, viewNormal));
+    viewTangent = normalize(cross(viewNormal, viewBinormal)); // note, now we need to re-cross to derive tangent again because it wasn't orthonormal
+    mat3 tbn = mat3(viewTangent, viewBinormal, viewNormal);
+
+    viewNormal = normalize(tbn * (normalTex * 2.0 - 1.0));
+#endif
+
+
+#if !PER_PIXEL_LIGHTING
+    gl_FragData[0] *= lighting;
+#else
+    gl_FragData[0] *= doLighting(passViewPos, normalize(viewNormal), passColor);
+#endif
+
+    float fogValue = clamp((depth - gl_Fog.start) * gl_Fog.scale, 0.0, 1.0);
+    gl_FragData[0].xyz = mix(gl_FragData[0].xyz, gl_Fog.color.xyz, fogValue);
+}

files/shaders/terrain_vertex.glsl

@@ -0,0 +1,36 @@
+#version 120
+
+varying vec2 uv;
+varying float depth;
+
+#define PER_PIXEL_LIGHTING (@normalMap || @forcePPL)
+
+#if !PER_PIXEL_LIGHTING
+varying vec4 lighting;
+#else
+varying vec3 passViewPos;
+varying vec3 passViewNormal;
+varying vec4 passColor;
+#endif
+
+#include "lighting.glsl"
+
+void main(void)
+{
+    gl_Position = gl_ModelViewProjectionMatrix * gl_Vertex;
+    depth = gl_Position.z;
+
+    vec4 viewPos = (gl_ModelViewMatrix * gl_Vertex);
+    gl_ClipVertex = viewPos;
+    vec3 viewNormal = normalize((gl_NormalMatrix * gl_Normal).xyz);
+
+#if !PER_PIXEL_LIGHTING
+    lighting = doLighting(viewPos.xyz, viewNormal, gl_Color);
+#else
+    passViewPos = viewPos.xyz;
+    passViewNormal = viewNormal;
+    passColor = gl_Color;
+#endif
+
+    uv = gl_MultiTexCoord0.xy;
+}