imagelib.c

第一次上传

LOAD BMP

============================================================================
*/


/*

// we can't just use these structures, because
// compiler structure alignment will not be portable
// on this unaligned stuff

typedef struct tagBITMAPFILEHEADER { // bmfh 
        WORD    bfType;				// BM
        DWORD   bfSize; 
        WORD    bfReserved1; 
        WORD    bfReserved2; 
        DWORD   bfOffBits; 
} BITMAPFILEHEADER; 
 
typedef struct tagBITMAPINFOHEADER{ // bmih 
   DWORD  biSize; 
   LONG   biWidth; 
   LONG   biHeight; 
   WORD   biPlanes; 
   WORD   biBitCount 
   DWORD  biCompression; 
   DWORD  biSizeImage; 
   LONG   biXPelsPerMeter; 
   LONG   biYPelsPerMeter; 
   DWORD  biClrUsed; 
   DWORD  biClrImportant; 
} BITMAPINFOHEADER; 
 
typedef struct tagBITMAPINFO { // bmi 
   BITMAPINFOHEADER bmiHeader; 
   RGBQUAD          bmiColors[1]; 
} BITMAPINFO; 

typedef struct tagBITMAPCOREHEADER { // bmch 
        DWORD   bcSize; 
        WORD    bcWidth; 
        WORD    bcHeight; 
        WORD    bcPlanes; 
        WORD    bcBitCount; 
} BITMAPCOREHEADER; 
 
typedef struct _BITMAPCOREINFO {    // bmci 
        BITMAPCOREHEADER  bmciHeader; 
        RGBTRIPLE         bmciColors[1]; 
} BITMAPCOREINFO; 
 
*/

/*
==============
LoadBMP
==============
*/
void LoadBMP (const char *filename, byte **pic, byte **palette, int *width, int *height)
{
	byte	*out;
	FILE	*fin;
	int		i;
    int		bfSize; 
    int		bfOffBits; 
	int		structSize;
    int		bcWidth; 
    int     bcHeight; 
    int	    bcPlanes; 
    int		bcBitCount; 
	byte	bcPalette[1024];
	qboolean	flipped;

	fin = fopen (filename, "rb");
	if (!fin) {
		Error ("Couldn't read %s", filename);
	}

	i = fgetLittleShort (fin);
	if (i != 'B' + ('M'<<8) ) {
		Error ("%s is not a bmp file", filename);
	}

	bfSize = fgetLittleLong (fin);
	fgetLittleShort(fin);
	fgetLittleShort(fin);
	bfOffBits = fgetLittleLong (fin);

	// the size will tell us if it is a
	// bitmapinfo or a bitmapcore
	structSize = fgetLittleLong (fin);
	if (structSize == 40) {
		// bitmapinfo
        bcWidth = fgetLittleLong(fin); 
        bcHeight= fgetLittleLong(fin); 
        bcPlanes = fgetLittleShort(fin); 
        bcBitCount = fgetLittleShort(fin); 

		fseek (fin, 24, SEEK_CUR);

		if (palette) {
			fread (bcPalette, 1, 1024, fin);
			*palette = malloc(768);

			for (i = 0 ; i < 256 ; i++) {
				(*palette)[i * 3 + 0] = bcPalette[i * 4 + 2];
				(*palette)[i * 3 + 1] = bcPalette[i * 4 + 1];
				(*palette)[i * 3 + 2] = bcPalette[i * 4 + 0];
			}
		}
	} else if (structSize == 12) {
		// bitmapcore
        bcWidth = fgetLittleShort(fin); 
        bcHeight= fgetLittleShort(fin); 
        bcPlanes = fgetLittleShort(fin); 
        bcBitCount = fgetLittleShort(fin); 

		if (palette) {
			fread (bcPalette, 1, 768, fin);
			*palette = malloc(768);

			for (i = 0 ; i < 256 ; i++) {
				(*palette)[i * 3 + 0] = bcPalette[i * 3 + 2];
				(*palette)[i * 3 + 1] = bcPalette[i * 3 + 1];
				(*palette)[i * 3 + 2] = bcPalette[i * 3 + 0];
			}
		}
	} else {
		Error ("%s had strange struct size", filename);
	}
	
	if (bcPlanes != 1) {
		Error ("%s was not a single plane image", filename);
	}

	if (bcBitCount != 8) {
		Error ("%s was not an 8 bit image", filename);
	}

	if (bcHeight < 0) {
		bcHeight = -bcHeight;
		flipped = qtrue;
	} else {
		flipped = qfalse;
	}

	if (width)
		*width = bcWidth;
	if (height)
		*height = bcHeight;

	if (!pic) {
		fclose (fin);
		return;
	}

	out = malloc ( bcWidth * bcHeight );
	*pic = out;
	fseek (fin, bfOffBits, SEEK_SET);

	if (flipped) {
		for (i = 0 ; i < bcHeight ; i++) {
			fread (out + bcWidth * (bcHeight - 1 - i), 1, bcWidth, fin);
		}
	} else {
		fread (out, 1, bcWidth*bcHeight, fin);
	}

	fclose (fin);
}


/*
============================================================================

LOAD IMAGE

============================================================================
*/

/*
==============
Load256Image

Will load either an lbm or pcx, depending on extension.
Any of the return pointers can be NULL if you don't want them.
==============
*/
void Load256Image (const char *name, byte **pixels, byte **palette,
				   int *width, int *height)
{
	char	ext[128];

	ExtractFileExtension (name, ext);
	if (!Q_stricmp (ext, "lbm"))
	{
		LoadLBM (name, pixels, palette);
		if (width)
			*width = bmhd.w;
		if (height)
			*height = bmhd.h;
	}
	else if (!Q_stricmp (ext, "pcx"))
	{
		LoadPCX (name, pixels, palette, width, height);
	}
	else if (!Q_stricmp (ext, "bmp"))
	{
		LoadBMP (name, pixels, palette, width, height);
	}
	else
		Error ("%s doesn't have a known image extension", name);
}


/*
==============
Save256Image

Will save either an lbm or pcx, depending on extension.
==============
*/
void Save256Image (const char *name, byte *pixels, byte *palette,
				   int width, int height)
{
	char	ext[128];

	ExtractFileExtension (name, ext);
	if (!Q_stricmp (ext, "lbm"))
	{
		WriteLBMfile (name, pixels, width, height, palette);
	}
	else if (!Q_stricmp (ext, "pcx"))
	{
		WritePCXfile (name, pixels, width, height, palette);
	}
	else
		Error ("%s doesn't have a known image extension", name);
}




/*
============================================================================

TARGA IMAGE

============================================================================
*/

typedef struct _TargaHeader {
	unsigned char 	id_length, colormap_type, image_type;
	unsigned short	colormap_index, colormap_length;
	unsigned char	colormap_size;
	unsigned short	x_origin, y_origin, width, height;
	unsigned char	pixel_size, attributes;
} TargaHeader;

/*
=============
LoadTGABuffer
=============
*/
void LoadTGABuffer ( byte *buffer, byte **pic, int *width, int *height)
{
	int		columns, rows, numPixels;
	byte	*pixbuf;
	int		row, column;
	byte	*buf_p;
	TargaHeader	targa_header;
	byte		*targa_rgba;

	*pic = NULL;

	buf_p = buffer;

	targa_header.id_length = *buf_p++;
	targa_header.colormap_type = *buf_p++;
	targa_header.image_type = *buf_p++;
	
	targa_header.colormap_index = LittleShort ( *(short *)buf_p );
	buf_p += 2;
	targa_header.colormap_length = LittleShort ( *(short *)buf_p );
	buf_p += 2;
	targa_header.colormap_size = *buf_p++;
	targa_header.x_origin = LittleShort ( *(short *)buf_p );
	buf_p += 2;
	targa_header.y_origin = LittleShort ( *(short *)buf_p );
	buf_p += 2;
	targa_header.width = LittleShort ( *(short *)buf_p );
	buf_p += 2;
	targa_header.height = LittleShort ( *(short *)buf_p );
	buf_p += 2;
	targa_header.pixel_size = *buf_p++;
	targa_header.attributes = *buf_p++;

	if (targa_header.image_type!=2 
		&& targa_header.image_type!=10
		&& targa_header.image_type != 3 ) 
	{
		Error("LoadTGA: Only type 2 (RGB), 3 (gray), and 10 (RGB) TGA images supported\n");
	}

	if ( targa_header.colormap_type != 0 )
	{
		Error("LoadTGA: colormaps not supported\n" );
	}

	if ( ( targa_header.pixel_size != 32 && targa_header.pixel_size != 24 ) && targa_header.image_type != 3 )
	{
		Error("LoadTGA: Only 32 or 24 bit images supported (no colormaps)\n");
	}

	columns = targa_header.width;
	rows = targa_header.height;
	numPixels = columns * rows;

	if (width)
		*width = columns;
	if (height)
		*height = rows;

	targa_rgba = malloc (numPixels*4);
	*pic = targa_rgba;

	if (targa_header.id_length != 0)
		buf_p += targa_header.id_length;  // skip TARGA image comment
	
	if ( targa_header.image_type==2 || targa_header.image_type == 3 )
	{ 
		// Uncompressed RGB or gray scale image
		for(row=rows-1; row>=0; row--) 
		{
			pixbuf = targa_rgba + row*columns*4;
			for(column=0; column<columns; column++) 
			{
				unsigned char red,green,blue,alphabyte;
				switch (targa_header.pixel_size) 
				{
					
				case 8:
					blue = *buf_p++;
					green = blue;
					red = blue;
					*pixbuf++ = red;
					*pixbuf++ = green;
					*pixbuf++ = blue;
					*pixbuf++ = 255;
					break;

				case 24:
					blue = *buf_p++;
					green = *buf_p++;
					red = *buf_p++;
					*pixbuf++ = red;
					*pixbuf++ = green;
					*pixbuf++ = blue;
					*pixbuf++ = 255;
					break;
				case 32:
					blue = *buf_p++;
					green = *buf_p++;
					red = *buf_p++;
					alphabyte = *buf_p++;
					*pixbuf++ = red;
					*pixbuf++ = green;
					*pixbuf++ = blue;
					*pixbuf++ = alphabyte;
					break;
				default:
					//Error("LoadTGA: illegal pixel_size '%d' in file '%s'\n", targa_header.pixel_size, name );
					break;
				}
			}
		}
	}
	else if (targa_header.image_type==10) {   // Runlength encoded RGB images
		unsigned char red,green,blue,alphabyte,packetHeader,packetSize,j;

		red = 0;
		green = 0;
		blue = 0;
		alphabyte = 0xff;

		for(row=rows-1; row>=0; row--) {
			pixbuf = targa_rgba + row*columns*4;
			for(column=0; column<columns; ) {
				packetHeader= *buf_p++;
				packetSize = 1 + (packetHeader & 0x7f);
				if (packetHeader & 0x80) {        // run-length packet
					switch (targa_header.pixel_size) {
						case 24:
								blue = *buf_p++;
								green = *buf_p++;
								red = *buf_p++;
								alphabyte = 255;
								break;
						case 32:
								blue = *buf_p++;
								green = *buf_p++;
								red = *buf_p++;
								alphabyte = *buf_p++;
								break;
						default:
							//Error("LoadTGA: illegal pixel_size '%d' in file '%s'\n", targa_header.pixel_size, name );
							break;
					}
	
					for(j=0;j<packetSize;j++) {
						*pixbuf++=red;
						*pixbuf++=green;
						*pixbuf++=blue;
						*pixbuf++=alphabyte;
						column++;
						if (column==columns) { // run spans across rows
							column=0;
							if (row>0)
								row--;
							else
								goto breakOut;
							pixbuf = targa_rgba + row*columns*4;
						}
					}
				}
				else {                            // non run-length packet
					for(j=0;j<packetSize;j++) {
						switch (targa_header.pixel_size) {
							case 24:
									blue = *buf_p++;
									green = *buf_p++;
									red = *buf_p++;
									*pixbuf++ = red;
									*pixbuf++ = green;
									*pixbuf++ = blue;
									*pixbuf++ = 255;
									break;
							case 32:
									blue = *buf_p++;
									green = *buf_p++;
									red = *buf_p++;
									alphabyte = *buf_p++;
									*pixbuf++ = red;
									*pixbuf++ = green;
									*pixbuf++ = blue;
									*pixbuf++ = alphabyte;
									break;
							default:
								//Sys_Printf("LoadTGA: illegal pixel_size '%d' in file '%s'\n", targa_header.pixel_size, name );
								break;
						}
						column++;
						if (column==columns) { // pixel packet run spans across rows
							column=0;
							if (row>0)
								row--;
							else
								goto breakOut;
							pixbuf = targa_rgba + row*columns*4;
						}						
					}
				}
			}
			breakOut:;
		}
	}

	//free(buffer);
}



/*
=============
LoadTGA
=============
*/
void LoadTGA (const char *name, byte **pixels, int *width, int *height)
{
	byte			*buffer;
  int nLen;
	//
	// load the file
	//
	nLen = LoadFile ( ( char * ) name, (void **)&buffer);
	if (nLen == -1) 
  {
		Error ("Couldn't read %s", name);
  }

  LoadTGABuffer(buffer, pixels, width, height);

}


/*
================
WriteTGA
================
*/
void WriteTGA (const char *filename, byte *data, int width, int height) {
	byte	*buffer;
	int		i;
	int		c;
	FILE	*f;

	buffer = malloc(width*height*4 + 18);
	memset (buffer, 0, 18);
	buffer[2] = 2;		// uncompressed type
	buffer[12] = width&255;
	buffer[13] = width>>8;
	buffer[14] = height&255;
	buffer[15] = height>>8;
	buffer[16] = 32;	// pixel size

	// swap rgb to bgr
	c = 18 + width * height * 4;
	for (i=18 ; i<c ; i+=4)
	{
		buffer[i] = data[i-18+2];		// blue
		buffer[i+1] = data[i-18+1];		// green
		buffer[i+2] = data[i-18+0];		// red
		buffer[i+3] = data[i-18+3];		// alpha
	}

	f = fopen (filename, "wb");
	fwrite (buffer, 1, c, f);
	fclose (f);

	free (buffer);
}

/*
============================================================================

LOAD32BITIMAGE

============================================================================
*/

/*
==============
Load32BitImage

Any of the return pointers can be NULL if you don't want them.
==============
*/
void Load32BitImage (const char *name, unsigned **pixels,  int *width, int *height)
{
	char	ext[128];
	byte	*palette;
	byte	*pixels8;
	byte	*pixels32;
	int		size;
	int		i;
	int		v;

	ExtractFileExtension (name, ext);
	if (!Q_stricmp (ext, "tga")) {
		LoadTGA (name, (byte **)pixels, width, height);
	} else {
		Load256Image (name, &pixels8, &palette, width, height);
		if (!pixels) {
			return;
		}
		size = *width * *height;
		pixels32 = malloc(size * 4);
		*pixels = (unsigned *)pixels32;
		for (i = 0 ; i < size ; i++) {
			v = pixels8[i];
			pixels32[i*4 + 0] = palette[ v * 3 + 0 ];
			pixels32[i*4 + 1] = palette[ v * 3 + 1 ];
			pixels32[i*4 + 2] = palette[ v * 3 + 2 ];
			pixels32[i*4 + 3] = 0xff;
		}
	}
}