OpenGL Programming Guide Sample program 2-15 complete code

#include "stdafx.h"
#include <windows.h>
#include <GL/glew.h>
#include <GL/glut.h>
#define Freeglut_static
#include <GL/freeglut.h>
#pragma COMMENT (linker, "/nodefaultlib:libc.lib")
#define BUFFER_OFFSET (offset) ((const glubyte *) NULL + (offset))

#define XStart-0.8
#define XEND 0.8
#define YStart-0.8
#define YEND 0.8
#define Numxpoints 11
#define Numypoints 11
#define NUMPOINTS (numxpoints * numypoints)
#define NUMPOINTSPERSTRIP (2 * numxpoints)
#define NUMSTRIPS (NUMYPOINTS-1)
#define RESTARTINDEX 0xFFFF
Glfloat color[6][3]={
{1.0,1.0,1.0},{1.0,0.0,0.0},{1.0,1.0,0.0},
{0.0,1.0,0.0},{0.0,1.0,1.0},{0.0,0.0,1.0}
};
void Init () {
Gluint Vbo, Ebo;
glfloat* vertices = 0;
glushort* indices = 0;
Glgenbuffers (1, &AMP;VBO);
Glbindbuffer (Gl_array_buffer, VBO);
Glbufferdata (Gl_array_buffer, 6 * numpoints * sizeof (glfloat), NULL, Gl_static_draw);
vertices = (glfloat*) glmapbuffer (Gl_array_buffer, gl_write_only);
if (vertices = = NULL) {
Exit (Exit_failure);
}
else{
int i;
Int J;
Glfloat dx = (glfloat) (Xend-xstart)/(NUMXPOINTS-1);
Glfloat dy = (glfloat) (Yend-ystart)/(NUMYPOINTS-1);
glfloat* tmp = vertices;
int n = 0;
for (j = 0; j < numypoints; ++j) {
Glfloat y = (glfloat) (Ystart + j * dy);
for (i = 0; i < numxpoints; ++i) {
Glfloat x = (glfloat) (Xstart + i * dx);
*tmp++ = color[(i+j)%6][0];
*tmp++ = color[(i+j)%6][1];
*tmp++ = color[(i+j)%6][2];
*tmp++ = x;
*tmp++ = y;
*tmp++ = 0;
}
}
Glunmapbuffer (Gl_array_buffer);
Glvertexpointer (3, gl_float, 6 * sizeof (glfloat), Buffer_offset (3 * sizeof (glfloat)));
Glcolorpointer (3, gl_float, 6 * sizeof (glfloat), Buffer_offset (0));
Glenableclientstate (Gl_vertex_array);
Glenableclientstate (Gl_color_array);
Glinterleavedarrays (gl_c3f_v3f, 0, 0);
}

Glgenbuffers (1, &ebo);
Glbindbuffer (Gl_element_array_buffer, Ebo);
Glbufferdata (Gl_element_array_buffer, Numstrips * (Numpointsperstrip + 1) * sizeof (Glushort), NULL, Gl_static_draw);
indices = (glushort*) glmapbuffer (Gl_element_array_buffer, gl_write_only);
if (indices = = NULL) {
Exit (Exit_failure);
}
else{
int i;
Int J;
glushort* index = indices;
for (j = 0; j < numstrips; ++j) {
Glushort Bottomrow = j * numypoints;
Glushort Toprow = Bottomrow + numypoints;
for (i = 0; i < numxpoints; ++i) {
*index++ = Toprow + i;
*index++ = Bottomrow + i;
}
*index++ = Restartindex;
}
Glunmapbuffer (Gl_element_array_buffer);
}
Glprimitiverestartindex (Restartindex);
Glenable (Gl_primitive_restart);
}

void display () {
Glclear (Gl_color_buffer_bit | Gl_depth_buffer_bit);
Glpolygonmode (Gl_front_and_back, gl_line);
glcolor3f (1, 1, 1);
Gldrawelements (Gl_triangle_strip, Numstrips * (Numpointsperstrip + 1), Gl_unsigned_short, Buffer_offset (0));
Glutswapbuffers ();
}
void reshape (int w, int h) {
Glviewport (0, 0, W, h);
Glmatrixmode (gl_projection);
Glloadidentity ();
gluortho2d (0.0, W, 0.0, h);
}
void Keyboardfunc (unsigned char key, int x, int y) {
Std::cout << key << x << y << Std::endl;
}
void Mouse (int button, int state, int x, int y) {
Switch (Button)
{
Case Glut_left_button:
if (state = = Glut_down) {
Glutidlefunc (NULL);
}
Break
Case Glut_right_button:
if (state = = Glut_down) {
Glutidlefunc (NULL);
}
Break
Default
Break
}
}
void Move (int x, int y) {
Std::cout << x << y << Std::endl;
}
int main (int argc, char** argv) {
Glutinit (&AMP;ARGC, argv);
Glutinitdisplaymode (glut_double | GLUT_RGB);
Glutinitwindowsize (250, 250);
Glutinitwindowposition (100, 100);
Glutinitcontextversion (3, 0);
Glutcreatewindow ("Hello");
Glewinit ();
Init ();
Glutdisplayfunc (display);
Glutreshapefunc (reshape);
Glutmousefunc (mouse);
Glutmotionfunc (move);
Glutkeyboardfunc (Keyboardfunc);
Glutmainloop ();
return 0;
}