PBO

#include <GL/glew.h>
#include <GL/freeglut.h>
#include <iostream>

GLuint pboID[];
GLuint textureID;

const int IMAGE_WIDTH = ;
const int IMAGE_HEIGHT = ;
const int CHANNEL_COUNT = ;
const int DATA_SIZE = IMAGE_WIDTH * IMAGE_HEIGHT * CHANNEL_COUNT;
GLubyte * imageData = ;

float cameraAngleX;
float cameraAngleY;
float cameraDistance = -5.0;  

bool mouseLeftDown;
bool mouseRightDown;
float LastXPos;
float LastYPos;  

void InitGL()
{
 glEnable(GL_TEXTURE_2D);
 glShadeModel(GL_SMOOTH);
 glClearColor(0.0, 0.0, 0.0, 1.0);

 glGenTextures(, &textureID);
 glBindTexture(GL_TEXTURE_2D, textureID);
 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_CLAMP);
 glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_CLAMP);
 glTexImage2D(GL_TEXTURE_2D, , GL_RGBA8, IMAGE_WIDTH, IMAGE_HEIGHT, , GL_BGRA, GL_UNSIGNED_BYTE, (GLvoid *)(imageData));
 glBindTexture(GL_TEXTURE_2D, );

 glGenBuffers(, pboID);
 glBindBuffer(GL_PIXEL_UNPACK_BUFFER, pboID[]);
 glBufferData(GL_PIXEL_UNPACK_BUFFER, DATA_SIZE, , GL_STREAM_DRAW);
 glBindBuffer(GL_PIXEL_UNPACK_BUFFER, pboID[]);
 glBufferData(GL_PIXEL_UNPACK_BUFFER, DATA_SIZE, , GL_STREAM_DRAW);
 glBindBuffer(GL_PIXEL_UNPACK_BUFFER, );
}

void UpdatePixels(GLubyte* dst, int size)
{
 static int color = ;  

 if(!dst)
  return;  

 int* ptr = (int*)dst;
 for(int i = ; i < IMAGE_HEIGHT; ++i)
 {
  for(int j = ; j < IMAGE_WIDTH; ++j)
  {
   *ptr = color;
   ptr++;
  }
  color += ;
 }
 ++color;
}  

void PaintGL()
{
 static int index = ;
 int nextIndex = ;
 index = (index + ) % ;
 nextIndex = (index + ) % ;
 glBindTexture(GL_TEXTURE_2D, textureID);
 glBindBuffer(GL_PIXEL_UNPACK_BUFFER, pboID[index]);

 glTexSubImage2D(GL_TEXTURE_2D, , , , IMAGE_WIDTH, IMAGE_HEIGHT, GL_BGRA, GL_UNSIGNED_BYTE, );
 glBindBuffer(GL_PIXEL_UNPACK_BUFFER, pboID[nextIndex]);
 glBufferData(GL_PIXEL_UNPACK_BUFFER, DATA_SIZE, , GL_STREAM_DRAW);
 GLubyte * ptr = (GLubyte *)glMapBuffer(GL_PIXEL_UNPACK_BUFFER, GL_WRITE_ONLY);
 if (ptr)
 {
  UpdatePixels(ptr, DATA_SIZE);
  glUnmapBuffer(GL_PIXEL_UNPACK_BUFFER);
 }
 glBindBuffer(GL_PIXEL_UNPACK_BUFFER, );
 glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
 glPushMatrix();

 glTranslatef(, , cameraDistance);
 glRotatef(cameraAngleX, , , );
 glRotatef(cameraAngleY, , , );      

 glBindTexture(GL_TEXTURE_2D, textureID);
 glColor4f(, , , );
 glBegin(GL_QUADS);
 glNormal3f(, , );
 glTexCoord2f(0.0f, 0.0f);   glVertex3f(-1.0f, -1.0f, 0.0f);
 glTexCoord2f(1.0f, 0.0f);   glVertex3f( 1.0f, -1.0f, 0.0f);
 glTexCoord2f(1.0f, 1.0f);   glVertex3f( 1.0f,  1.0f, 0.0f);
 glTexCoord2f(0.0f, 1.0f);   glVertex3f(-1.0f,  1.0f, 0.0f);
 glEnd();  

 glBindTexture(GL_TEXTURE_2D, );  

 glPopMatrix();  

 glutSwapBuffers();
}

void ResizeGL(int w, int h)
{
 if (h == )
  h = ;
 glViewport(, , w, h);
 glMatrixMode(GL_PROJECTION);
 glLoadIdentity();
 gluPerspective(45.0, w/h, 1.0, 100.0);
 glMatrixMode(GL_MODELVIEW);
 glLoadIdentity();
}

void mouse(int button, int state, int x, int y)
{  

 if (button == GLUT_LEFT_BUTTON && state == GLUT_DOWN)
 {
  mouseLeftDown = true;  

  LastXPos = x;
  LastYPos = y;
 }  

 if (button == GLUT_RIGHT_BUTTON && state == GLUT_UP)
 {
  mouseRightDown = true;
 }
}
void mouseMotion(int x, int y)
{
 if (mouseLeftDown)
 {
  cameraAngleX += GLfloat(y - LastYPos)/GLfloat(20.0);
  cameraAngleY += GLfloat(x - LastXPos)/GLfloat(20.0);
  LastYPos = y;
  LastXPos = x;
 }
}  

int main(int argc, char ** argv)
{
 glutInit(&argc, argv);
 glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGBA);
 glutInitWindowSize(, );
 glutCreateWindow("PBO");
 GLenum res = glewInit();
 if (res != GLEW_OK)
 {
  std::cout << glewGetErrorString(res) << std::endl;
  return EXIT_FAILURE;
 }

 InitGL();
 glutDisplayFunc(PaintGL);
 glutReshapeFunc(ResizeGL);
 glutMouseFunc(mouse);
 glutMotionFunc(mouseMotion);
 glutMainLoop();
 glDeleteBuffers(, pboID);
 glDeleteTextures(, &textureID);
 delete [] imageData;
 return EXIT_SUCCESS;
}