Jump to content
  • Advertisement
Sign in to follow this  
souhail

Drawing over a loaded picture

This topic is 3498 days old which is more than the 365 day threshold we allow for new replies. Please post a new topic.

If you intended to correct an error in the post then please contact us.

Recommended Posts

I loaded a ppm image and I'm having trouble drawing over this image, I just need to draw square or shapes over it and update coordinates. Here is my code: #include<windows.h> // use as needed for your system #include <stdio.h> #include <stdlib.h> #include<gl/Gl.h> #include<gl/glut.h> int n; int m; int *image; void myInit (void) { glClearColor ( 1.0, 1.0, 1.0 , 1.0); glColor3f ( 1.0f, 0.0f, 0.0f ); glPointSize ( 4.0 ); glMatrixMode ( GL_PROJECTION ); glLoadIdentity ( ); gluOrtho2D ( 0.0, 400.0, 1.0, 400.0 ); } void display(void) { //glClear ( GL_COLOR_BUFFER_BIT ); glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); glRasterPos2i(0,0);glMatrixMode(GL_MODELVIEW); glDrawPixels(n,m,GL_RGB, GL_UNSIGNED_INT, image); //glFlush ( ); glPushMatrix(); glBegin(GL_QUADS); glNormal3f(0.0, 1.0f, 0.0f); glTexCoord2f(0.0f, 0.0f); glVertex3f(-2.5f, -2.5f, 2.5f); glTexCoord2f(1.0f, 0.0f); glVertex3f(2.5f, -2.5f, 2.5f); glTexCoord2f(1.0f, 1.0f); glVertex3f(2.5f, -2.5f, -2.5f); glTexCoord2f(0.0f, 1.0f); glVertex3f(-2.5f, -2.5f, -2.5f); glEnd(); glPopMatrix(); glutSwapBuffers(); } void myreshape(int h, int w) { glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); glMatrixMode (GL_PROJECTION); glLoadIdentity(); gluOrtho2D(0.0, (GLfloat) n, 0.0, (GLfloat) m); glMatrixMode(GL_MODELVIEW); glLoadIdentity(); glViewport(0,0,h,w); } int main(int argc, char**argv) { FILE *fd; int k, nm; char c; char b[70]; float s; char red, green, blue; int x, y; fd = fopen("au.ppm", "r"); if(fd == 0) { exit(0); } fscanf(fd, "%s", b); if((b[0] != 'P') || (b[1] != '6')) { printf("%s is not a PPM file!\n", b); exit(0); } fscanf(fd, "%c", &c); fscanf(fd, "%c", &c); while(c == '#') { fscanf(fd, "%[^\n]", b); printf("%s\n", b); fscanf(fd, "%c", &c); printf("%c", c); } ungetc(c,fd); fscanf(fd, "%d %d %d", &n, &m, &k); printf("%d rows %d colums max value = %d\n", n, m, k); nm = n*m; image = malloc(3*sizeof(GLint)*nm); s = 255./k; for(x = 0; x < m; x++) { for(y = n-1; y >= 0; y--) { fscanf(fd, "%c", &red); fscanf(fd, "%c", &green); fscanf(fd, "%c", &blue); image[3*nm - 3*(x*n +y) -3] = green; image[3*nm - 3*(x*n +y) -2] = blue; image[3*nm - 3*(x*n +y) -1] = red; } } glutInit(&argc, argv); //glutInitDisplayMode(GLUT_SINGLE | GLUT_RGB); glutInitDisplayMode(GLUT_DOUBLE |GLUT_RGB ); glutInitWindowSize(n,m); glutInitWindowPosition(0,0); glutCreateWindow("image"); glutReshapeFunc(myreshape); glutDisplayFunc(display); glPixelTransferf(GL_RED_SCALE, s); glPixelTransferf(GL_GREEN_SCALE, s); glPixelTransferf(GL_BLUE_SCALE, s); glPixelStorei(GL_UNPACK_SWAP_BYTES, GL_TRUE); glClearColor(1.0, 1.0, 1.0, 1.0); myInit ( ); glutMainLoop ( ); } Can somebody help me with this. The only output I'm getting is the image. Any OpenGL experts? Thank you so much!

Share this post


Link to post
Share on other sites
Advertisement
Sign in to follow this  

  • Advertisement
×

Important Information

By using GameDev.net, you agree to our community Guidelines, Terms of Use, and Privacy Policy.

Participate in the game development conversation and more when you create an account on GameDev.net!

Sign me up!