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//#include "stdafx.h"
#include<glut.h>
#include<windows.h>
#include<math.h>//<cmath>replace with cmath if it doesn't work
#include <stdlib.h>
//Global variables
BITMAPINFO *info; // Bitmap information
GLubyte *pixels; // Actual pixel data
GLubyte * ReadBitmap(const char *filename,BITMAPINFO **info);
float xpos, ypos;
void Draw()//SEED IN: glutDisplayFunc
{ glClear(GL_COLOR_BUFFER_BIT);
glColor3f(1.0,1.0,0.0);
glBegin(GL_LINES);//XXXSHAPE);
glVertex3f(0.25, 0.25, 0.0);
glVertex3f(0.75, 0.75, 0.0);
glEnd();
glFlush();
glutSwapBuffers();//IMPORTANT for double buffering
}
void Display(void)
{
glClear(GL_COLOR_BUFFER_BIT);
glRasterPos2f(100,ypos);
// Draw the loaded pixels
glDrawPixels(info->bmiHeader.biWidth,
info->bmiHeader.biHeight,
GL_BGR_EXT, GL_UNSIGNED_BYTE, pixels);
glFlush();
glutSwapBuffers();
//120 is max Y value in our logical coordinate system
ypos = ypos + 0.1;
if (ypos >= 120.)
ypos = 0;
//Force a redisplay
glutPostRedisplay();
}
/********
initilise display
*********/
void Initialize()
{
glClearColor(0.0,0.0,0.0,0.0);
glMatrixMode(GL_PROJECTION);
glLoadIdentity();
glOrtho(0.0,1.0,0.0,1.0,-1.0,1.0);
xpos = 60;
ypos = 0;
}
/********
main program
*********/
int main(int argc, char* argv[])
{
start:
glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGB);
glutInitWindowSize (320, 240);
glutInitWindowPosition(200, 200);
glutCreateWindow("Display My Images");
Initialize();
glutDisplayFunc(Display);
//read in the pixel data
if (argc > 1)
pixels = ReadBitmap(argv[1],&info);
else
pixels = ReadBitmap("smiley.bmp", &info);
glutMainLoop();
goto start;
return 0;
}
/********
Read Bitmap information. Return the final BITMAP PIXEL values
*********/
GLubyte * ReadBitmap(const char * filename,BITMAPINFO **info)
{
FILE *fp; /* Open file pointer */
GLubyte *pixels; /* Bitmap pixel bits */
int imgsize; /* Size of bitmap image */
int infosize; /* Size of header information */
BITMAPFILEHEADER header; /* File header */
//try opening the file; use "rb" mode to read a binary file.
if ((fp = fopen(filename, "rb")) == NULL)
return (NULL);
//Read the file header
if (fread(&header, sizeof(BITMAPFILEHEADER), 1, fp) < 1)
{
//Couldn't read the file header
fclose(fp);
return (NULL);
}
if(header.bfType != 'MB') /* Check for BM reversed... */
{
//Not a bitmap file
fclose(fp);
return (NULL);
}
infosize = header.bfOffBits - sizeof(BITMAPFILEHEADER);
if ((*info = (BITMAPINFO *)malloc(infosize)) == NULL)
{
fclose(fp);
return (NULL);
}
if (fread(*info, 1, infosize, fp)< infosize)
{
free(*info);
fclose(fp);
return (NULL);
}
/*Now that we have all the header info read in,
* allocate memory for the bitmap and read it in...
*/
imgsize = (*info)->bmiHeader.biSizeImage;
//sometimes imagesize is not set in files
if (imgsize == 0)
imgsize = ((*info)->bmiHeader.biWidth *
(*info)->bmiHeader.biBitCount + 7) / 8 *
abs ((*info)->bmiHeader.biHeight);
if ((pixels = (unsigned char *)malloc(imgsize)) == NULL)
{
free(*info);
fclose(fp);
return (NULL);
}
fclose(fp);
return (pixels);
}
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