Opengl Samples - Copy

#include <stdio.h> #include <string.h> #include <stdlib.h> #include <GL/glut.h> #include "rgb.h" GLenum doubleBuffer; GLint windW = 300, windH = 300; RGBImageRec *image = NULL; float point[3]; float zoom; GLint x, y; static void Init(void) { glClearColor(0.0, 0.0, 0.0, 0.0); x = 0; y = windH; zoom = 1.8; } static void Reshape(int width, int height) { windW = width; windH = height; glViewport(0, 0, windW, windH); glMatrixMode(GL_PROJECTION); glLoadIdentity(); gluOrtho2D(0, windW, 0, windH); glMatrixMode(GL_MODELVIEW); } static void Key(unsigned char key, int x, int y) { switch (key) { case 27: exit(0); } } static void SpecialKey(int key, int x, int y) { switch (key) { case GLUT_KEY_UP: zoom += 0.2; glutPostRedisplay(); break; case GLUT_KEY_DOWN: zoom -= 0.2; if (zoom < 0.2) { zoom = 0.2; } glutPostRedisplay(); break; } } static void Mouse(int button, int state, int mouseX, int mouseY) { if (state == GLUT_DOWN) { x = mouseX; y = mouseY; glutPostRedisplay(); } } static void Draw(void) { glClear(GL_COLOR_BUFFER_BIT); point[0] = (windW / 2) - (image->sizeX / 2); point[1] = (windH / 2) - (image->sizeY / 2); point[2] = 0; glRasterPos3fv(point); glPixelStorei(GL_UNPACK_ALIGNMENT, 1); glPixelZoom(1.0, 1.0); glDrawPixels(image->sizeX, image->sizeY, GL_RGB, GL_UNSIGNED_BYTE, image->data); point[0] = (float)x; point[1] = windH - (float)y; point[2] = 0.0; glRasterPos3fv(point); glPixelZoom(zoom, zoom); glCopyPixels((windW/2)-(image->sizeX/2), (windH/2)-(image->sizeY/2), image->sizeX, image->sizeY, GL_COLOR); if (doubleBuffer) { glutSwapBuffers(); } else { glFlush(); } } static void Args(int argc, char **argv) { GLint i; doubleBuffer = GL_FALSE; for (i = 1; i < argc; i++) { if (strcmp(argv[i], "-sb") == 0) { doubleBuffer = GL_FALSE; } else if (strcmp(argv[i], "-db") == 0) { doubleBuffer = GL_TRUE; } else if (strcmp(argv[i], "-f") == 0) { if (i+1 >= argc || argv[i+1][0] == '-') { printf("-f (No file name).\n"); exit(1); } else { image = rgbImageLoad(argv[++i]); if (image == NULL) { printf("-f (bad file name).\n"); exit(1); } } } } } int main(int argc, char **argv) { GLenum type; glutInit(&argc, argv); Args(argc, argv); if (image == NULL) { printf("No texture file.\n"); exit(1); } type = GLUT_RGB; type |= (doubleBuffer) ? GLUT_DOUBLE : GLUT_SINGLE; glutInitDisplayMode(type); glutInitWindowSize(windW, windH); glutCreateWindow("Copy Test"); Init(); glutReshapeFunc(Reshape); glutKeyboardFunc(Key); glutSpecialFunc(SpecialKey); glutMouseFunc(Mouse); glutDisplayFunc(Draw); glutMainLoop(); }