Bitmap creator for ST7565 based displays

fontmaker.c

//#include<windows.h>
#define GLUT_DISABLE_ATEXIT_HACK
#include <GL/glut.h>
#include <stdio.h>
#include <string.h>

#define background	1, 1, 1
#define foreground	0, 0, 0

unsigned int width = 5;
unsigned int height = 8;
unsigned int byteCount = (height/8);

int cx, cy;//click mouse pos
int gw,gh = 0;//window width and height

uint8_t *matrix = NULL;

void init( void ){
  glClearColor(background, 0.0);
}

void reshape(int w, int h){
  gw=w;gh=h;
  if (w == 0) w = 1;
  if (h == 0) h = 1;
  glViewport(0, 0, (GLsizei)w, (GLsizei)h);
  glMatrixMode(GL_PROJECTION);
  glLoadIdentity();
  gluOrtho2D(0.,1.,0.,1.);
  glutPostRedisplay();
  glutInitWindowSize(320,320);

}

void drawBox(float ax, float ay, float bx, float by, float cx, float cy, float dx, float dy, float r, float g, float b)
{
    glBegin(GL_LINE_STRIP);
      glColor3f(r,g,b);  	/*kolor rysowania D_____ C	*/
      glVertex2f(ax,ay);	/*A(x,y)	  |     | 	*/
      glVertex2f(bx,by);	/*B(x,y)	  |     | 	*/
      glVertex2f(cx,cy);	/*C(x,y)	 A|_____|B	*/
      glVertex2f(dx,dy);
      glVertex2f(ax,ay);
    glEnd();
}

void drawRect(float ax, float ay, float bx, float by, float cx, float cy, float dx, float dy, float r, float g, float b)
{
    glBegin(GL_QUADS);
      glColor3f(r,g,b);  	/*kolor rysowania D_____ C	*/
      glVertex2f(ax,ay);	/*A(x,y)	  |     | 	*/
      glVertex2f(bx,by);	/*B(x,y)	  |     | 	*/
      glVertex2f(cx,cy);	/*C(x,y)	 A|_____|B	*/
      glVertex2f(dx,dy);
      glVertex2f(ax,ay);
    glEnd();
}
  
void display(void){
  glMatrixMode(GL_MODELVIEW);
  glLoadIdentity();
  glClear(GL_COLOR_BUFFER_BIT);
  float i,j;
  int k,l;
  int m;
  for(m = 0; m < byteCount; m++)
  {
    for(i = 0,k = 0; i < 1.; i+=1./width)	/* X axis */
    {
      for(j = (1./byteCount)*m, l = 0; j < (1./byteCount)*(m+1); j+=1./height)//end on 1, 0.5, 0.25, ...
      {
	drawBox(
	  i,     j,
	  i+1./width, j,
	  i+1./width, j+1./height,
	  i,      j+1./height,
	  foreground
	);
	if((matrix[k+((byteCount-m-1)*width)] & (1<<(height/byteCount-1-l))) != 0 )//divide by num of bytes per column
	  drawRect(
	    i,     j,
	    i+1./width, j,
	    i+1./width, j+1./height,
	    i,      j+1./height,
	    foreground
	  );
	l++;
      }
      k++;
    }
  }
  glFinish();
}

void mouseFunc(int btn, int state, int x, int y)
{
  int i;
  switch(btn)
  {
    case GLUT_LEFT_BUTTON:
      if(state==GLUT_UP)
      {
	//released
	int mx,my, mcx,mcy = 0;
	//release
	mx = x/(gw/width);if(mx>width)mx=-1;
	my = y/(gh/height);if(my>height)my=-1;
	//click
	mcx = cx/(gw/width);if(mcx>(width-1))mcx=-1;
	mcy = cy/(gh/height);if(mcy>(height-1))mcy=-1;
	for(i = 0; i < byteCount; i++)
	{
	  if(mx==mcx && my==mcy && mx>=0 && mcx>=0 && my>=0 && mcy>=0 && my<((i+1)*8))
	  {
	    matrix[mx+(width*i)]^=1<<my-(8*i);
	  }
	}
	glutPostRedisplay();
      }
      else if(state==GLUT_DOWN)
      {
	//clicked
	cx=x;
	cy=y;
      }
      break;
  }
}

void keyFunc(unsigned char key, int x, int y)
{
  int i,j;
  switch(key)
  {
    case 'r':
      memset(matrix,'\0',width*byteCount);
      glutPostRedisplay();
      break;
    case 'p':
      for(j = 0; j < byteCount; j++)
      {
	for(i = width*j; i < width*(j+1); i++)
	  printf("0x%02x ",matrix[i]);
	printf("\n");
      }
      break;
  }
}

int main( int argc, char** argv )
{
  if(argc>2)
  {
    width = atoi(argv[1]);
    height = atoi(argv[2]);
    byteCount = (height/8);
    if(height % 8 != 0)
    {
      fprintf(stderr,"Error: tried to use height that is not divisible by 8\n");
      return 1;
    }
  }
  matrix = (uint8_t*) malloc(width*byteCount);
  memset(matrix, 0x00, width*byteCount);
  int mode = GLUT_RGB | GLUT_SINGLE;
  glutInit( &argc, argv);
  glutInitDisplayMode(mode);
  glutInitWindowSize(320,448);
  glutInitWindowPosition(100,100);
  glutCreateWindow("glFontMaker");
  init();
  glutDisplayFunc(display);
  glutReshapeFunc(reshape);
  glutMouseFunc(mouseFunc);
  glutKeyboardFunc(keyFunc);
  glutMainLoop();
}