tesselation

A1/hellocube/cubewidget.cpp

@@ -21,7 +21,7 @@ void CubeWidget::initializeGL ()
     glClearColor(0.0, 0.0, 0.0, 0.0);
     glEnable(GL_DEPTH_TEST);
 
-
+    tesselation = 0;
     // enable default shading
     showFlat();
 
@@ -55,41 +55,73 @@ void CubeWidget::paintGL ( )
     GLfloat yellow[] = {1.0,1.0,0.0};
 
     glBegin(GL_QUADS);
+    float increment = 1.0/(pow(2,tesselation));
+
     setMaterial(red);
-    glVertex3f( 0.5f, 0.5f,-0.5f);
-    glVertex3f(-0.5f, 0.5f,-0.5f);
-    glVertex3f(-0.5f, 0.5f, 0.5f);
-    glVertex3f( 0.5f, 0.5f, 0.5f);
+    for (float x = -0.5; x < 0.5 ; x+= increment) {
+        for (float y = -0.5; y < 0.5 ; y+= increment ) {
+        glVertex3f( x+increment, 0.5f,y);
+        glVertex3f(x, 0.5f,y);
+        glVertex3f(x, 0.5f, y+increment);
+        glVertex3f( x+increment, 0.5f, y+increment);
+        }
+    }
+
 
     setMaterial(magenta);
     glVertex3f( 0.5f,-0.5f, 0.5f);
     glVertex3f(-0.5f,-0.5f, 0.5f);
     glVertex3f(-0.5f,-0.5f,-0.5f);
     glVertex3f( 0.5f,-0.5f,-0.5f);
+    for (float x = -0.5; x < 0.5 ; x+= increment) {
+        for (float y = -0.5; y < 0.5 ; y+= increment ) {
+        glVertex3f( x+increment, -0.5f,y+increment);
+        glVertex3f(x, -0.5f,y+increment);
+        glVertex3f(x, -0.5f, y);
+        glVertex3f( x+increment, -0.5f, y);
+        }
+    }
 
     setMaterial(green);
-    glVertex3f( 0.5f, 0.5f, 0.5f);
-    glVertex3f(-0.5f, 0.5f, 0.5f);
-    glVertex3f(-0.5f,-0.5f, 0.5f);
-    glVertex3f( 0.5f,-0.5f, 0.5f);
+    for (float x = -0.5; x < 0.5 ; x+= increment) {
+        for (float y = -0.5; y < 0.5 ; y+= increment ) {
+        glVertex3f( x+increment,y+increment, 0.5f);
+        glVertex3f(x, y+increment, 0.5f);
+        glVertex3f(x,  y, 0.5f);
+        glVertex3f( x+increment, y, 0.5f);
+        }
+    }
 
     setMaterial(yellow);
-    glVertex3f( 0.5f,-0.5f,-0.5f);
-    glVertex3f(-0.5f,-0.5f,-0.5f);
-    glVertex3f(-0.5f, 0.5f,-0.5f);
-    glVertex3f( 0.5f, 0.5f,-0.5f);
+    for (float x = -0.5; x < 0.5 ; x+= increment) {
+        for (float y = -0.5; y < 0.5 ; y+= increment ) {
+            glVertex3f( x+increment,y, -0.5f);
+            glVertex3f(x, y,-0.5f);
+            glVertex3f(x, y+increment,-0.5f);
+            glVertex3f( x+increment,y+increment, -0.5f);
+        }
+    }
+
 
     setMaterial(blue);
-    glVertex3f(-0.5f, 0.5f, 0.5f);
-    glVertex3f(-0.5f, 0.5f,-0.5f);
-    glVertex3f(-0.5f,-0.5f,-0.5f);
-    glVertex3f(-0.5f,-0.5f, 0.5f);
+    for (float x = -0.5; x < 0.5 ; x+= increment) {
+        for (float y = -0.5; y < 0.5 ; y+= increment ) {
+        glVertex3f( -0.5f, x+increment,y+increment);
+        glVertex3f( -0.5f,x+increment,y);
+        glVertex3f( -0.5f,x, y);
+        glVertex3f(  -0.5f,x, y+increment);
+        }
+    }
 
     setMaterial(cyan);
-    glVertex3f( 0.5f, 0.5f,-0.5f);
-    glVertex3f( 0.5f, 0.5f, 0.5f);
-    glVertex3f( 0.5f,-0.5f, 0.5f);
-    glVertex3f( 0.5f,-0.5f,-0.5f);
+    for (float x = -0.5; x < 0.5 ; x+= increment) {
+        for (float y = -0.5; y < 0.5 ; y+= increment ) {
+        glVertex3f( 0.5f, x+increment,y);
+        glVertex3f( 0.5f,x+increment,y+increment);
+        glVertex3f( 0.5f,x, y+increment);
+        glVertex3f(  0.5f,x, y);
+        }
+    }
     glEnd();
 }
 
@@ -126,7 +158,7 @@ void CubeWidget::showWireframe()
     glDisable(GL_CULL_FACE);
 
      glPolygonMode(GL_FRONT_AND_BACK,GL_LINE);
-     repaint();
+     updateGL();
 }
 
 void CubeWidget::showFlat()
@@ -135,7 +167,7 @@ void CubeWidget::showFlat()
     glShadeModel(GL_FLAT);
     glEnable(GL_CULL_FACE);
     glPolygonMode(GL_FRONT_AND_BACK,GL_FILL);
-    repaint();
+    updateGL();
 }
 
 void CubeWidget::showGouraut()
@@ -144,7 +176,7 @@ void CubeWidget::showGouraut()
     glShadeModel(GL_SMOOTH);
     glEnable(GL_CULL_FACE);
     glPolygonMode(GL_FRONT_AND_BACK,GL_FILL);
-    repaint();
+    updateGL();
 }
 
 void CubeWidget::showPhong()
@@ -156,6 +188,8 @@ void CubeWidget::showPhong()
 
 void CubeWidget::setTessellation(int t)
 {
+    tesselation = t;
+    updateGL();
     qDebug()<<"Tesselation" << t;
 }
 

A1/hellocube/cubewidget.h

@@ -5,6 +5,7 @@
 #include <QtOpenGL>
 #include <QGLFunctions>
 #include <QOpenGLFunctions>
+#include <math.h>
 
 
 
@@ -34,6 +35,7 @@ public slots:
     void setTessellation(int t );
 
 private:
+    int tesselation;
     void perspective(GLdouble fovy, GLdouble aspect, GLdouble zNear, GLdouble zFar);
     void setMaterial(GLfloat *color );
 };