ray marching

A3/controler.cpp

@@ -176,7 +176,7 @@ void Controler::addVolume(QString filePath){
 
     int count = 0;
     //  std::cout<<std::hex;
-    int printLine = 150;
+    int printLine = 400;// z/2;
 
     for(int k = 0; k < z; k++)
     {

A3/display.frag

 uniform sampler2D Texture;
-uniform sampler2D TextureID;
-uniform int active;
+uniform sampler2D PickID;
 
+uniform sampler2D StartRay;
+uniform sampler2D StopRay;
+uniform sampler3D volumeData;
 
-varying vec4 qt_TexCoord0;
+uniform bool MIP;
+
+
+vec4 transfer(float scalar){
+    return vec4(scalar);
+}
 
 void main(void)
 {
-    gl_FragColor = texture2D(Texture,gl_TexCoord[0].st);
-    //gl_FragColor = texture2D(TextureID,gl_TexCoord[0].st)/255;
-    //gl_FragColor = vec4(active);
+    // gl_FragColor = vec4(gl_TexCoord[0].st,0,1);
+    //gl_FragColor = texture2D(PickID,gl_TexCoord[0].st);
+    //gl_FragColor = texture2D(StartRay,gl_TexCoord[0].st);
+    gl_FragColor = vec4(texture2D(StopRay,gl_TexCoord[0].st).xyz,1);
+
+
    // gl_FragColor = vec4(gl_TexCoord[0].st,0,1);
 
+    vec3 front = texture2D(StartRay,gl_TexCoord[0].st).xyz;
+    vec3 back = texture2D(StopRay,gl_TexCoord[0].st).xyz;
+
+
+    if(front == back){
+        gl_FragColor = vec4(texture2D(Texture,gl_TexCoord[0].st).xyz,1);
+    }else{
+
+        vec3 ray = back-front;
+         float rayLength = length(ray);
+         vec3 stepVector = 0.01 * ray/rayLength;
+
+         vec3 pos = front;
+         vec4 dst = vec4(0);
+         float maxfloat = 0;
+
+         while (dst.a < 1 && rayLength > 0) {
+
+             float density = texture3D(volumeData, pos).x;
+             maxfloat = max(density,maxfloat);
+
+             vec4 src = transfer(density);
+
+             src.rgb *= src.a;
+
+             dst = (1.0 - dst.a) * src + dst;
+             pos += stepVector;
+             rayLength -= 0.01;
+         }
+
+         if(MIP) {
+            gl_FragColor = transfer(maxfloat);
+         }else{
+            gl_FragColor = dst;
+         }
+
+
+        // gl_FragColor = vec4(gl_TexCoord[0].xyz,1);
+        //gl_FragColor = vec4(vec3(count),1);
+        //gl_FragColor = vec4(normalize(step),1);
+        //gl_FragColor = vec4(normalize(gl_ModelViewProjectionMatrixInverse*vec4(0,1,0,0.0)));
+        //gl_FragColor = vec4(texture3D(volumeData,vec3(front.xy,0.5)).x);
+    }
 }
 
+

A3/glview.cpp

@@ -56,8 +56,9 @@ void GLView::initShader()
     shader->addShader(vertex);
     shader->addShader(fragment);
     shader->bindAttributeLocation("pickID",4);
-    if(!shader->link())
+    if(!shader->link()){
         qCritical()<< "Linking  failed"<<shader->log();
+    }
 
 
 
@@ -72,8 +73,10 @@ void GLView::initShader()
     displayShader = new QGLShaderProgram(this);
     displayShader->addShader(vertex);
     displayShader->addShader(fragment);
-    if(!displayShader->link())
-        qCritical()<< "Linking  failed"<<displayShader->log();
+    if(!displayShader->link()){
+        qCritical()<< "Linking 2 failed:"<<displayShader->log();
+    }
+
 }
 
 void GLView::home(){
@@ -93,8 +96,8 @@ void GLView::paintGL ()
     shader->bind();
     if(useFBO){
         glBindFramebuffer(GL_FRAMEBUFFER,fbo);
-        GLenum buffers[] = {GL_COLOR_ATTACHMENT0,GL_COLOR_ATTACHMENT1};
-        glDrawBuffers(2,buffers);
+        GLenum buffers[] = {GL_COLOR_ATTACHMENT0,GL_COLOR_ATTACHMENT1,GL_COLOR_ATTACHMENT2,GL_COLOR_ATTACHMENT3};
+        glDrawBuffers(4,buffers);
 
         //http://stackoverflow.com/questions/7207422/setting-up-opengl-multiple-render-targets
     }
@@ -102,6 +105,7 @@ void GLView::paintGL ()
 
     glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
     glEnable(GL_DEPTH_TEST);
+    glDisable(GL_CULL_FACE);
 
     glViewport(0,0,this->width(),this->height());
 
@@ -110,9 +114,7 @@ void GLView::paintGL ()
     glMatrixMode (GL_PROJECTION);
     glLoadIdentity ();
 
-    glActiveTexture(GL_TEXTURE0);
-    glBindTexture(GL_TEXTURE_3D,texture3D);
-    displayShader->setUniformValue("volumeData",0);
+
 
     shader->setUniformValue("shaded",true);
 
@@ -172,9 +174,21 @@ void GLView::paintGL ()
 
         glActiveTexture(GL_TEXTURE1);
         glBindTexture(GL_TEXTURE_2D,picID);
-        displayShader->setUniformValue("TextureID",1);
+        displayShader->setUniformValue("PickID",1);
+
+        glActiveTexture(GL_TEXTURE2);
+        glBindTexture(GL_TEXTURE_2D,startRay);
+        displayShader->setUniformValue("StartRay",2);
+
+        glActiveTexture(GL_TEXTURE3);
+        glBindTexture(GL_TEXTURE_2D,stopRay);
+        displayShader->setUniformValue("StopRay",3);
 
-        displayShader->setUniformValue("active",scene->getActive()->getID());
+        glActiveTexture(GL_TEXTURE4);
+        glBindTexture(GL_TEXTURE_3D,texture3D);
+        displayShader->setUniformValue("volumeData",4);
+
+        //displayShader->setUniformValue("active",scene->getActive()->getID());
 
         glBegin (GL_QUADS);
         glTexCoord2d(0,0);
@@ -315,7 +329,7 @@ void GLView::resizeGL(int width , int height )
     glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL);
 
 
-    // Create the color buffer
+    // Create the pcik buffer
     glGenTextures(1, &picID);
     glBindTexture(GL_TEXTURE_2D, picID);
     glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
@@ -325,6 +339,26 @@ void GLView::resizeGL(int width , int height )
     glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL);
 
 
+    // Create the pcik startRay
+    glGenTextures(1, &startRay);
+    glBindTexture(GL_TEXTURE_2D, startRay);
+    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL);
+
+    // Create the pcik stopRay
+    glGenTextures(1, &stopRay);
+    glBindTexture(GL_TEXTURE_2D, stopRay);
+    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP_TO_EDGE);
+    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP_TO_EDGE);
+    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR);
+    glTexParameterf(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_LINEAR);
+    glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, NULL);
+
+
+
     // Create the depth buffer
     glGenRenderbuffers(1, &depth);
     glBindRenderbuffer(GL_RENDERBUFFER, depth);
@@ -332,6 +366,8 @@ void GLView::resizeGL(int width , int height )
 
     glFramebufferTexture2D(GL_FRAMEBUFFER,GL_COLOR_ATTACHMENT0,GL_TEXTURE_2D,color,0);
     glFramebufferTexture2D(GL_FRAMEBUFFER,GL_COLOR_ATTACHMENT1,GL_TEXTURE_2D,picID,0);
+    glFramebufferTexture2D(GL_FRAMEBUFFER,GL_COLOR_ATTACHMENT2,GL_TEXTURE_2D,startRay,0);
+    glFramebufferTexture2D(GL_FRAMEBUFFER,GL_COLOR_ATTACHMENT3,GL_TEXTURE_2D,stopRay,0);
     glFramebufferRenderbuffer(GL_FRAMEBUFFER,GL_DEPTH_ATTACHMENT,GL_RENDERBUFFER,depth);
 
     GLenum err = glCheckFramebufferStatus(GL_FRAMEBUFFER);

A3/glview.h

@@ -58,6 +58,9 @@ private:
     GLuint picID;
     GLuint depth;
 
+    GLuint startRay;
+    GLuint stopRay;
+
     GLuint texture3D;
 
 

A3/hellocube.pro.user

 <?xml version="1.0" encoding="UTF-8"?>
 <!DOCTYPE QtCreatorProject>
-<!-- Written by QtCreator 3.5.1, 2015-12-03T11:54:44. -->
+<!-- Written by QtCreator 3.5.1, 2015-12-05T11:07:00. -->
 <qtcreator>
  <data>
   <variable>EnvironmentId</variable>

A3/mainwindow.cpp

@@ -303,7 +303,7 @@ MainWindow::MainWindow(QWidget *parent)
 
 void MainWindow::initScene(){
     //scene->simpleScene();
-    controler->addVolume("D:/Projekte/GraPa/A3/lobster.raw");
+   // controler->addVolume("D:/Projekte/GraPa/A3/MRI-head.raw");
 
     timer->stop();
 }

A3/phong.frag

@@ -12,14 +12,7 @@ void main(void)
 {
     vec3 V = normalize(-position);
 
-    if(volume){
-
-       // gl_FragData[0] = vec4(gl_TexCoord[0].xyz,1);
-
-        gl_FragData[0] = vec4(texture3D(volumeData,gl_TexCoord[0].xyz).x);
-
-    }
-    else if(shaded){
+     if(shaded){
         vec3 N = normalize(normal);
         vec3 L = normalize(gl_LightSource[0].position.xyz-position);
 
@@ -39,10 +32,23 @@ void main(void)
         vec4 color = (Iamb + Idiff + Ispec );
 
         gl_FragData[0] =  color;
-    }
-    else
+    } else
         gl_FragData[0] = vec4(1,1,0,1);
 
-    gl_FragData[1] = pick;
-    //gl_FragData[1] = vec4(abs(normal),1);
+    //gl_FragData[1] = pick;
+    gl_FragData[1] = vec4(abs(normal),1);
+
+    if(volume){
+        if(gl_FrontFacing){
+            gl_FragData[2] = gl_TexCoord[0];
+        //    gl_FragData[3] = vec4(0);
+
+        } else{
+         //   gl_FragData[2] = vec4(0);
+            gl_FragData[3] = gl_TexCoord[0];
+        }
+    } else {
+        gl_FragData[2] = vec4(0,0,0,1);
+        gl_FragData[3] = vec4(0,0,0,1);
+    }
 }

A3/scenevolume.cpp

@@ -37,6 +37,16 @@ void SceneVolume::draw(QGLShaderProgram *shader){
 
     shader->setUniformValue("volume", true);
 
+    QMatrix4x4 mat = QMatrix4x4();
+    mat.rotate(getGlobalRotation().conjugate());
+    glMultMatrixf(mat.data());
+
+ //   shader->setUniformValue("volumeRot",mat);
+
+    glDisable(GL_DEPTH_TEST);
+    glBlendFunc(GL_SRC_ALPHA, GL_ONE_MINUS_SRC_ALPHA);
+    glEnable( GL_BLEND );
+
     float x = lx/2;
     float y = ly/2;
     float z = lz/2;
@@ -113,9 +123,48 @@ void SceneVolume::draw(QGLShaderProgram *shader){
     glVertex3f(  x,  -y,  -z);
     glEnd();
 
+    shader->setUniformValue("volume", false);
+    shader->setUniformValue("shaded", false);
+    glLineWidth(2);
+    if(true){
+        glBegin(GL_LINES);
+        glVertex3f(  x,  y, -z);
+        glVertex3f(  x,  y, z);
+        glVertex3f(  -x,  y, -z);
+        glVertex3f(  -x,  y, z);
+        glVertex3f(  x,  -y, -z);
+        glVertex3f(  x,  -y, z);
+        glVertex3f(  -x,  -y, -z);
+        glVertex3f(  -x,  -y, z);
+
+        glVertex3f(  x,  -y, z);
+        glVertex3f(  x,  y, z);
+        glVertex3f(  -x,  -y, z);
+        glVertex3f(  -x,  y, z);
+        glVertex3f(  x,  -y, -z);
+        glVertex3f(  x,  y, -z);
+        glVertex3f(  -x,  -y, -z);
+        glVertex3f(  -x,  y, -z);
+
+        glVertex3f(  -x,  y, z);
+        glVertex3f(  x,  y, z);
+        glVertex3f(  -x,  -y, z);
+        glVertex3f(  x,  -y, z);
+        glVertex3f(  -x,  y, -z);
+        glVertex3f(  x,  y, -z);
+        glVertex3f(  -x,  -y, -z);
+        glVertex3f(  x,  -y, -z);
+        glEnd();
+
+    }
+    shader->setUniformValue("shaded", true);
+
+     glEnable(GL_DEPTH_TEST);
+     glDisable( GL_BLEND );
+
     glPopMatrix();
 
-    shader->setUniformValue("volume", false);
+
 
 
 }