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/*
* Copyright (C) 2008 Tunsgten Graphics,Inc. All Rights Reserved.
*/
/*
* Test GL_OES_draw_texture
* Brian Paul
* August 2008
*/
#define GL_GLEXT_PROTOTYPES
#include <math.h>
#include <stdlib.h>
#include <stdio.h>
#include <string.h>
#include <GLES/gl.h>
#include <GLES/glext.h>
#include "eglut.h"
static GLfloat view_posx = 10.0, view_posy = 20.0;
static GLfloat width = 200, height = 200;
static GLboolean animate = GL_FALSE;
static int win;
static void
draw(void)
{
glClear(GL_COLOR_BUFFER_BIT);
glDrawTexfOES(view_posx, view_posy, 0.0, width, height);
}
/* new window size or exposure */
static void
reshape(int width, int height)
{
GLfloat ar = (GLfloat) width / (GLfloat) height;
glViewport(0, 0, (GLint) width, (GLint) height);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
#ifdef GL_VERSION_ES_CM_1_0
glFrustumf(-ar, ar, -1, 1, 5.0, 60.0);
#else
glFrustum(-ar, ar, -1, 1, 5.0, 60.0);
#endif
glMatrixMode(GL_MODELVIEW);
glLoadIdentity();
glTranslatef(0.0, 0.0, -15.0);
}
static float
dist(GLuint i, GLuint j, float x, float y)
{
return sqrt((i-x) * (i-x) + (j-y) * (j-y));
}
static void
make_smile_texture(void)
{
#define SZ 128
GLenum Filter = GL_LINEAR;
GLubyte image[SZ][SZ][4];
GLuint i, j;
GLint cropRect[4];
for (i = 0; i < SZ; i++) {
for (j = 0; j < SZ; j++) {
GLfloat d_mouth = dist(i, j, SZ/2, SZ/2);
GLfloat d_rt_eye = dist(i, j, SZ*3/4, SZ*3/4);
GLfloat d_lt_eye = dist(i, j, SZ*3/4, SZ*1/4);
if (d_rt_eye < SZ / 8 || d_lt_eye < SZ / 8) {
image[i][j][0] = 20;
image[i][j][1] = 50;
image[i][j][2] = 255;
image[i][j][3] = 255;
}
else if (i < SZ/2 && d_mouth < SZ/3) {
image[i][j][0] = 255;
image[i][j][1] = 20;
image[i][j][2] = 20;
image[i][j][3] = 255;
}
else {
image[i][j][0] = 200;
image[i][j][1] = 200;
image[i][j][2] = 200;
image[i][j][3] = 255;
}
}
}
glActiveTexture(GL_TEXTURE0); /* unit 0 */
glBindTexture(GL_TEXTURE_2D, 42);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, SZ, SZ, 0,
GL_RGBA, GL_UNSIGNED_BYTE, image);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, Filter);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, Filter);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
cropRect[0] = 0;
cropRect[1] = 0;
cropRect[2] = SZ;
cropRect[3] = SZ;
glTexParameteriv(GL_TEXTURE_2D, GL_TEXTURE_CROP_RECT_OES, cropRect);
#undef SZ
}
static void
init(void)
{
const char *ext = (char *) glGetString(GL_EXTENSIONS);
if (!strstr(ext, "GL_OES_draw_texture")) {
fprintf(stderr, "Sorry, this program requires GL_OES_draw_texture");
exit(1);
}
glClearColor(0.4, 0.4, 0.4, 0.0);
make_smile_texture();
glEnable(GL_TEXTURE_2D);
}
static void
idle(void)
{
if (animate) {
view_posx += 1.0;
view_posy += 2.0;
eglutPostRedisplay();
}
}
static void
key(unsigned char key)
{
switch (key) {
case ' ':
animate = !animate;
break;
case 'w':
width -= 1.0f;
break;
case 'W':
width += 1.0f;
break;
case 'h':
height -= 1.0f;
break;
case 'H':
height += 1.0f;
break;
case 27:
eglutDestroyWindow(win);
exit(0);
break;
default:
break;
}
}
static void
special_key(int key)
{
switch (key) {
case EGLUT_KEY_LEFT:
view_posx -= 1.0;
break;
case EGLUT_KEY_RIGHT:
view_posx += 1.0;
break;
case EGLUT_KEY_UP:
view_posy += 1.0;
break;
case EGLUT_KEY_DOWN:
view_posy -= 1.0;
break;
default:
break;
}
}
int
main(int argc, char *argv[])
{
eglutInitWindowSize(400, 300);
eglutInitAPIMask(EGLUT_OPENGL_ES1_BIT);
eglutInit(argc, argv);
win = eglutCreateWindow("drawtex");
eglutIdleFunc(idle);
eglutReshapeFunc(reshape);
eglutDisplayFunc(draw);
eglutKeyboardFunc(key);
eglutSpecialFunc(special_key);
init();
eglutMainLoop();
return 0;
}
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