Changeset 2859 for GTP/trunk/App/Demos/Vis/FriendlyCulling/src/SsaoShader.cpp

Timestamp:

08/21/08 16:31:03 (16 years ago)

Author:

mattausch

Message:

 

File:

• GTP/trunk/App/Demos/Vis/FriendlyCulling/src/SsaoShader.cpp (modified) (1 diff)

GTP/trunk/App/Demos/Vis/FriendlyCulling/src/SsaoShader.cpp

@@ -1 @@
-#include "DeferredShader.h"
+#include "SsaoShader.h"
+#include "FrameBufferObject.h"
+#include "RenderState.h"
+#include "SampleGenerator.h"
+
 
 using namespace std;
 
+GLenum mrt[] = {GL_COLOR_ATTACHMENT0_EXT, GL_COLOR_ATTACHMENT1_EXT, GL_COLOR_ATTACHMENT2_EXT};
 
 namespace CHCDemoEngine
 {
 
+static CGprogram sCgSsaoProgram = NULL;
+
+static CGparameter sColorsTexParam;
+static CGparameter sPositionsTexParam;
+static CGparameter sNormalsTexParam;
+static CGparameter sOldModelViewProjMatrixParam;
+static CGparameter sMaxDepthParam;
+static CGparameter sSamplesParam; 
+static CGparameter sOldTexParam;
+static CGparameter sNoiseTexParam;
+static CGparameter sNoiseMultiplierParam;
+static CGparameter sExpFactorParam;
+
+
+#define NUM_SAMPLES 16
+
+// ssao random spherical samples
+static Sample2 samples[NUM_SAMPLES];
+
+
+static void PrintGLerror(char *msg)
+{
+        GLenum errCode;
+        const GLubyte *errStr;
+        
+        if ((errCode = glGetError()) != GL_NO_ERROR) 
+        {
+                errStr = gluErrorString(errCode);
+                fprintf(stderr,"OpenGL ERROR: %s: %s\n", errStr, msg);
+        }
+}
+
+
+/** Generate poisson disc distributed sample points on the unit disc
+*/
+static void GenerateSamples()
+{
+        static PoissonDiscSampleGenerator poisson(NUM_SAMPLES, 1.0f);
+        poisson.Generate((Sample2 *)samples);
+}
+
+
+SsaoShader::SsaoShader(int w, int h, float expFactor, float scaleFactor):
+mWidth(w), mHeight(h), mExpFactor(expFactor), mScaleFactor(scaleFactor)
+{}
+
+
+void SsaoShader::Init(CGcontext context)
+{
+        
+        ///////////////
+
+        sCgSsaoProgram = 
+                cgCreateProgramFromFile(context, 
+                                                                CG_SOURCE,
+                                                                "src/shaders/deferred.cg", 
+                                                                RenderState::sCgFragmentProfile,
+                                                                "main_ssao",
+                                                                NULL);
+
+        if (sCgSsaoProgram != NULL)
+        {
+                cgGLLoadProgram(sCgSsaoProgram);
+
+                // we need size of texture for scaling
+                sPositionsTexParam = cgGetNamedParameter(sCgSsaoProgram, "positions");  
+                sColorsTexParam = cgGetNamedParameter(sCgSsaoProgram, "colors");  
+                sNormalsTexParam = cgGetNamedParameter(sCgSsaoProgram, "normals");  
+                sNoiseTexParam = cgGetNamedParameter(sCgSsaoProgram, "noiseTexture");
+                sNoiseMultiplierParam = cgGetNamedParameter(sCgSsaoProgram, "noiseMultiplier");
+                sOldModelViewProjMatrixParam = cgGetNamedParameter(sCgSsaoProgram, "oldModelViewProj");
+                sMaxDepthParam = cgGetNamedParameter(sCgSsaoProgram, "maxDepth");
+                sExpFactorParam = cgGetNamedParameter(sCgSsaoProgram, "expFactor");
+
+                sSamplesParam = cgGetNamedParameter(sCgSsaoProgram, "samples");
+                sOldTexParam = cgGetNamedParameter(sCgSsaoProgram, "oldTex");  
+
+                // generate samples for ssao kernel
+                GenerateSamples(); 
+                cgGLSetParameterArray2f(sSamplesParam, 0, NUM_SAMPLES, (const float *)samples);
+        }
+        else
+                cerr << "ssao program failed to load" << endl;
+
+        PrintGLerror("init");
+}
+
+
+void SsaoShader::Render(FrameBufferObject *fbo, FrameBufferObject *fbo2)
+{
+        FirstPass(fbo, fbo2);
+        SecondPass(fbo, fbo2);
+}
+
+
+void SsaoShader::FirstPass(FrameBufferObject *fbo, FrameBufferObject *fbo2)
+{
+        GLuint positionsTex = fbo->GetColorBuffer(0)->GetTexture();
+        GLuint colorsTex = fbo->GetColorBuffer(0)->GetTexture();
+        GLuint normalsTex = fbo->GetColorBuffer(0)->GetTexture();
+
+        glPushAttrib(GL_VIEWPORT_BIT);
+        glViewport(0, 0, mWidth, mHeight);
+
+        glDrawBuffers(1, mrt);
+
+        glDisable(GL_ALPHA_TEST);
+        glDisable(GL_TEXTURE_2D);
+        glDisable(GL_LIGHTING);
+
+        glMatrixMode(GL_PROJECTION);
+        glPushMatrix();
+        glLoadIdentity();
+
+        glMatrixMode(GL_MODELVIEW);
+        glPushMatrix();
+        glLoadIdentity();
+
+        const float offs = 0.5f;
+
+        glOrtho(-offs, offs, -offs, offs, 0, 1);
+
+        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+
+        cgGLEnableProfile(RenderState::sCgFragmentProfile);
+
+        cgGLBindProgram(sCgSsaoProgram);
+
+        cgGLSetTextureParameter(sPositionsTexParam, positionsTex);
+        cgGLEnableTextureParameter(sPositionsTexParam);
+
+        cgGLSetTextureParameter(sColorsTexParam, colorsTex);
+        cgGLEnableTextureParameter(sColorsTexParam);
+
+        cgGLSetTextureParameter(sNormalsTexParam, normalsTex);
+        cgGLEnableTextureParameter(sNormalsTexParam);
+
+        cgGLSetTextureParameter(sNoiseTexParam, noiseTex);
+        cgGLEnableTextureParameter(sNoiseTexParam);
+
+        cgGLSetTextureParameter(sOldTexParam, oldTex);
+        cgGLEnableTextureParameter(sOldTexParam);
+
+        cgGLSetParameter1f(sNoiseMultiplierParam, RandomValue(3.0f, 17.0f));
+        
+        cgGLSetParameter1f(sMaxDepthParam, mScaleFactor);
+        cgGLSetParameter1f(sExpFactorParam, mExpFactor);
+
+
+        GenerateSamples(); 
+        cgGLSetParameterArray2f(sSamplesParam, 0, NUM_SAMPLES, (const float *)samples);
+
+        Vector3 tl, tr, bl, br;
+        ComputeViewVectors(tl, tr, bl, br);
+
+        glColor3f(1.0f, 1.0f, 1.0f);
+
+        glBegin(GL_QUADS);
+
+        // note: slightly larger texture hides ambient occlusion error on border but costs resolution
+        //float offs2 = 0.55f;
+        float offs2 = 0.5f;
+
+        glColor3f(bl.x, bl.y, bl.z); glTexCoord2f(0, 0); glVertex3f(-offs2, -offs2, -0.5f);
+        glColor3f(br.x, br.y, br.z); glTexCoord2f(1, 0); glVertex3f( offs2, -offs2, -0.5f);
+        glColor3f(tr.x, tr.y, tr.z); glTexCoord2f(1, 1); glVertex3f( offs2,  offs2, -0.5f);
+        glColor3f(tl.x, tl.y, tl.z); glTexCoord2f(0, 1); glVertex3f(-offs2,  offs2, -0.5f);
+
+        glEnd();
+
+        cgGLDisableTextureParameter(sColorsTexParamSsao);
+        cgGLDisableTextureParameter(sPositionsTexParamSsao);
+        cgGLDisableTextureParameter(sNormalsTexParamSsao);
+        cgGLDisableTextureParameter(sNoiseTexParamSsao);
+        cgGLDisableTextureParameter(sOldTexParamSsao);
+
+        cgGLDisableProfile(RenderState::sCgFragmentProfile);
+
+        glEnable(GL_LIGHTING);
+        glDisable(GL_TEXTURE_2D);
+
+        glMatrixMode(GL_PROJECTION);
+        glPopMatrix();
+
+        glMatrixMode(GL_MODELVIEW);
+        glPopMatrix();
+
+        glPopAttrib();
+
+        PrintGLerror("displaytexture");
+
+        glBindFramebufferEXT(GL_FRAMEBUFFER_EXT, 0);
+
+
+        PrintGLerror("ssao first pass");
+}
+
+
+void SsaoShader::SecondPass(FrameBufferObject *fbo, FrameBufferObject *fbo2)
+{
+        glEnable(GL_TEXTURE_2D);
+
+        glBindTexture(GL_TEXTURE_2D, fbo2->GetColorBuffer(0)->GetTexture());
+
+        glDisable(GL_LIGHTING);
+        
+        glMatrixMode(GL_PROJECTION);
+        glPushMatrix();
+        glLoadIdentity();
+
+        glMatrixMode(GL_MODELVIEW);
+        glPushMatrix();
+        glLoadIdentity();
+
+        const float offs = 0.5f;
+        glOrtho(-offs, offs, -offs, offs, 0, 1);
+        
+        glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+
+        glColor4f(1.0f, 1.0f, 1.0f, 1.0f);
+        glBegin(GL_QUADS);
+
+        glTexCoord2f(0, 0); glVertex3f(-offs, -offs, -0.5f);
+        glTexCoord2f(1, 0); glVertex3f( offs, -offs, -0.5f);
+        glTexCoord2f(1, 1); glVertex3f( offs,  offs, -0.5f);
+        glTexCoord2f(0, 1); glVertex3f(-offs,  offs, -0.5f);
+
+        glEnd();
+
+        glEnable(GL_LIGHTING);
+        glDisable(GL_TEXTURE_2D);
+        
+        glMatrixMode(GL_PROJECTION);
+        glPopMatrix();
+
+        glMatrixMode(GL_MODELVIEW);
+        glPopMatrix();
+
+        PrintGLerror("ssao second pass");
+}
+
+
+
 } // namespace