Bitmap loading in windows

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[b][red]This message was edited by the Gamekeeper at 2002-6-2 6:10:4[/red][/b][hr]

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[b][red]This message was edited by the Gamekeeper at 2002-6-2 6:10:14[/red][/b][hr]

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[b][red]This message was edited by the Gamekeeper at 2002-7-17 8:42:18[/red][/b][hr]
#include
#include

bool ReadBMP(char* filename, char** data, int* width, int* height);
bool WriteBMP(char* filename, char* data, int width, int height);

bool ReadBMP(char* filename, char** data, int* width, int* height)
{
FILE* file;
BITMAPFILEHEADER bfh;
BITMAPINFOHEADER bih;
int nbytes;
unsigned char extrabytes;
char reserved[4];
char* p2;
unsigned int scanbitcount;
file = fopen(filename, "rb");
if (!file) return false;
fread((void*)&bfh, sizeof(bfh), 1, file);
if (bfh.bfType != (('M' << 8) + 'B'))
{
fclose(file);
perror("This is not a valid bitmap!");
return false;
}
fread((void*)&bih, sizeof(bih), 1, file);
if (bih.biCompression != BI_RGB)
{
fclose(file);
perror("Can't handle compression!");
return false;
}
if (bih.biBitCount != 24)
{
fclose(file);
perror("Too few colors!");
return true;
}
nbytes = bih.biWidth * bih.biHeight * 3;
scanbitcount = bih.biWidth * 3;
extrabytes = scanbitcount % 4;
*data = new char[nbytes];
fseek(file, bfh.bfOffBits, 0);
if (extrabytes)
{
extrabytes = 4 - extrabytes;
p2 = *data;
for (int i = 0; i < nbytes; i += scanbitcount)
{
fread((void*)&p2[i], scanbitcount, 1, file);
fread((void*)reserved, 1, extrabytes, file);
}
}
else
{
fread((void*)*data, nbytes, 1, file);
}
fclose(file);
*width = bih.biWidth;
*height = bih.biHeight;
return true;
}

bool WriteBMP(char* filename, char* data, int width, int height)
{
FILE* file;
BITMAPFILEHEADER bfh;
BITMAPINFOHEADER bih;
unsigned long nbytes = width * height * 3;
unsigned short oh_size = sizeof(BITMAPFILEHEADER) + sizeof(BITMAPINFOHEADER);
unsigned char extrabytes = (width * 3) % 4;
unsigned char reserved = 0;
unsigned short scanbitcount;
bfh.bfType = ('M' << 8) + 'B';
bfh.bfSize = oh_size + nbytes;
bfh.bfOffBits = oh_size;
bfh.bfReserved1 = 0;
bfh.bfReserved2 = 0;
bih.biSize = sizeof(BITMAPINFOHEADER);
bih.biWidth = width;
bih.biHeight = height;
bih.biPlanes = 1;
bih.biBitCount = 24;
bih.biCompression = BI_RGB;
bih.biSizeImage = 0;
bih.biXPelsPerMeter = 0;
bih.biYPelsPerMeter = 0;
bih.biClrUsed = 0;
bih.biClrImportant = 0;
file = fopen(filename, "wb");
if (!file) return false;
fwrite((void*)&bfh, sizeof(bfh), 1, file);
fwrite((void*)&bih, sizeof(bih), 1, file);
if (extrabytes)
{
extrabytes = 4 - extrabytes;
for (int i = 0; i < nbytes; i += scanbitcount)
{
fwrite(&data[i], scanbitcount, 1, file);
fwrite(&reserved, 1, extrabytes, file);
}
}
else
{
fwrite(data, nbytes, 1, file);
}
fclose(file);
return true;
}