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/* $Id: image.c,v 1.3 1996/09/27 01:27:10 brianp Exp $ */
/*
* Mesa 3-D graphics library
* Version: 2.0
* Copyright (C) 1995-1996 Brian Paul
*
* This library is free software; you can redistribute it and/or
* modify it under the terms of the GNU Library General Public
* License as published by the Free Software Foundation; either
* version 2 of the License, or (at your option) any later version.
*
* This library is distributed in the hope that it will be useful,
* but WITHOUT ANY WARRANTY; without even the implied warranty of
* MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the GNU
* Library General Public License for more details.
*
* You should have received a copy of the GNU Library General Public
* License along with this library; if not, write to the Free
* Software Foundation, Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
*/
/*
* $Log: image.c,v $
* Revision 1.3 1996/09/27 01:27:10 brianp
* removed unused variables
*
* Revision 1.2 1996/09/26 22:35:10 brianp
* fixed a few compiler warnings from IRIX 6 -n32 and -64 compiler
*
* Revision 1.1 1996/09/13 01:38:16 brianp
* Initial revision
*
*/
#include <assert.h>
#include <stdlib.h>
#include <string.h>
#include "image.h"
#include "macros.h"
#include "pixel.h"
#include "types.h"
/*
* Flip the 8 bits in each byte of the given array.
*/
void gl_flip_bytes( GLubyte *p, GLuint n )
{
register GLuint i, a, b;
for (i=0;i<n;i++) {
b = (GLuint) p[i];
a = ((b & 0x01) << 7) |
((b & 0x02) << 5) |
((b & 0x04) << 3) |
((b & 0x08) << 1) |
((b & 0x10) >> 1) |
((b & 0x20) >> 3) |
((b & 0x40) >> 5) |
((b & 0x80) >> 7);
p[i] = (GLubyte) a;
}
}
/*
* Flip the order of the 2 bytes in each word in the given array.
*/
void gl_swap2( GLushort *p, GLuint n )
{
register GLuint i;
for (i=0;i<n;i++) {
p[i] = (p[i] >> 8) | ((p[i] << 8) & 0xff00);
}
}
/*
* Flip the order of the 4 bytes in each word in the given array.
*/
void gl_swap4( GLuint *p, GLuint n )
{
register GLuint i, a, b;
for (i=0;i<n;i++) {
b = p[i];
a = (b >> 24)
| ((b >> 8) & 0xff00)
| ((b << 8) & 0xff0000)
| ((b << 24) & 0xff000000);
p[i] = a;
}
}
/*
* Return the size, in bytes, of the given GL datatype.
* Return 0 if GL_BITMAP.
* Return -1 if invalid type enum.
*/
GLint gl_sizeof_type( GLenum type )
{
switch (type) {
case GL_BITMAP:
return 0;
case GL_UNSIGNED_BYTE:
return sizeof(GLubyte);
case GL_BYTE:
return sizeof(GLbyte);
case GL_UNSIGNED_SHORT:
return sizeof(GLushort);
case GL_SHORT:
return sizeof(GLshort);
case GL_UNSIGNED_INT:
return sizeof(GLuint);
case GL_INT:
return sizeof(GLint);
case GL_FLOAT:
return sizeof(GLfloat);
default:
return -1;
}
}
/*
* Return the number of components in a GL enum pixel type.
* Return -1 if bad format.
*/
GLint gl_components_in_format( GLenum format )
{
switch (format) {
case GL_COLOR_INDEX:
case GL_STENCIL_INDEX:
case GL_DEPTH_COMPONENT:
case GL_RED:
case GL_GREEN:
case GL_BLUE:
case GL_ALPHA:
case GL_LUMINANCE:
return 1;
case GL_LUMINANCE_ALPHA:
return 2;
case GL_RGB:
return 3;
case GL_RGBA:
return 4;
default:
return -1;
}
}
/*
* Return the address of a pixel in an image. Pixel unpacking/packing
* parameters are observed according to 'packing'.
* Input: image - start of image data
* width, height - size of image
* format - image format
* type - pixel component type
* packing - GL_TRUE = use packing params
* GL_FALSE = use unpacking params.
* row, column - location of pixel whose address is to be returned
* Return: address of pixel at (row,column) in image or NULL if error.
*/
GLvoid *gl_pixel_addr_in_image( GLcontext *ctx,
const GLvoid *image, GLsizei width,
GLsizei height, GLenum format, GLenum type,
GLboolean packing,
GLint row, GLint column )
{
GLint bytes_per_comp; /* bytes per component */
GLint comp_per_pixel; /* components per pixel */
GLint comps_per_row; /* components per row */
GLint pixels_per_row; /* pixels per row */
GLint alignment; /* 1, 2 or 4 */
GLint skiprows;
GLint skippixels;
GLubyte *pixel_addr;
/* Compute bytes per component */
bytes_per_comp = gl_sizeof_type( type );
if (bytes_per_comp<0) {
return NULL;
}
/* Compute number of components per pixel */
comp_per_pixel = gl_components_in_format( format );
if (comp_per_pixel<0) {
return NULL;
}
if (packing) {
/* Use PACKING parameters */
alignment = ctx->Pack.Alignment;
if (ctx->Pack.RowLength>0) {
pixels_per_row = ctx->Pack.RowLength;
}
else {
pixels_per_row = width;
}
skiprows = ctx->Pack.SkipRows;
skippixels = ctx->Pack.SkipPixels;
}
else {
/* Use UNPACKING parameters */
alignment = ctx->Unpack.Alignment;
if (ctx->Unpack.RowLength>0) {
pixels_per_row = ctx->Unpack.RowLength;
}
else {
pixels_per_row = width;
}
skiprows = ctx->Unpack.SkipRows;
skippixels = ctx->Unpack.SkipPixels;
}
if (type==GL_BITMAP) {
/* BITMAP data */
GLint bytes_per_row;
bytes_per_row = alignment
* CEILING( comp_per_pixel*pixels_per_row, 8*alignment );
pixel_addr = (GLubyte *) image
+ (skiprows + row) * bytes_per_row
+ (skippixels + column) / 8;
}
else {
/* Non-BITMAP data */
if (bytes_per_comp>=alignment) {
comps_per_row = comp_per_pixel * pixels_per_row;
}
else {
GLint bytes_per_row = bytes_per_comp * comp_per_pixel
* pixels_per_row;
comps_per_row = alignment / bytes_per_comp
* CEILING( bytes_per_row, alignment );
}
/* Copy/unpack pixel data to buffer */
pixel_addr = (GLubyte *) image
+ (skiprows + row) * comps_per_row * bytes_per_comp
+ (skippixels + column) * comp_per_pixel * bytes_per_comp;
}
return (GLvoid *) pixel_addr;
}
/*
* Unpack a 2-D image from user-supplied address, returning a pointer to
* a new gl_image struct.
* This function is always called by a higher-level unpack function such
* as gl_unpack_texsubimage() or gl_unpack_bitmap().
*
* Input: width, height - size in pixels
* components - number of components per pixel, ignored
* if srctype and desttype is BITMAP.
* srctype - GL_UNSIGNED_BYTE .. GL_FLOAT
* desttype - store image as GL_UNSIGNED_BYTE, GL_FLOAT, or GL_BITMAP.
* if GL_UNSIGNED_BYTE, srctype must be GL_UNSIGNED_BYTE.
* if GL_BITMAP, srctype must be GL_BITMAP.
* interleave - if TRUE, srctype and desttype must be GL_UNSIGNED_BYTE
* pixels - pointer to unpacked image.
*/
struct gl_image *gl_unpack_image( GLcontext *ctx,
GLint width, GLint height,
GLint components, GLenum srctype,
GLenum desttype,
const GLvoid *pixels,
GLboolean interleave )
{
if (srctype==GL_BITMAP || desttype==GL_BITMAP) {
struct gl_image *image;
GLint bytes, i, width_in_bytes;
GLubyte *buffer, *dst;
assert( srctype==GL_BITMAP );
assert( desttype==GL_BITMAP );
/* Alloc dest storage */
bytes = (width+7)/8 * height;
if (bytes>0 && pixels!=NULL) {
buffer = (GLubyte *) malloc( bytes );
if (!buffer) {
return NULL;
}
/* Copy/unpack pixel data to buffer */
width_in_bytes = CEILING( width, 8 );
dst = buffer;
for (i=0;i<height;i++) {
GLvoid *src = gl_pixel_addr_in_image( ctx, pixels, width, height,
GL_COLOR_INDEX, srctype,
GL_FALSE, i, 0 );
if (!src) {
free(buffer);
return NULL;
}
MEMCPY( dst, src, width_in_bytes );
dst += width_in_bytes;
}
/* Bit flipping */
if (ctx->Unpack.LsbFirst) {
gl_flip_bytes( buffer, bytes );
}
}
else {
/* a 'null' bitmap */
buffer = NULL;
}
image = (struct gl_image *) malloc( sizeof(struct gl_image) );
if (image) {
image->Width = width;
image->Height = height;
image->Components = 0;
image->Type = GL_BITMAP;
image->Interleaved = GL_FALSE;
image->Data = buffer;
}
else {
free( buffer );
return NULL;
}
return image;
}
else if (desttype==GL_UNSIGNED_BYTE) {
struct gl_image *image;
GLint width_in_bytes;
GLubyte *buffer, *dst;
GLint i;
GLenum format;
assert( srctype==GL_UNSIGNED_BYTE );
width_in_bytes = width * components * sizeof(GLubyte);
buffer = malloc( height * width_in_bytes );
if (!buffer) {
return NULL;
}
switch (components) {
case 1: format = GL_LUMINANCE; break;
case 2: format = GL_LUMINANCE_ALPHA; break;
case 3: format = GL_RGB; break;
case 4: format = GL_RGBA; break;
default: abort();
}
/* Copy/unpack pixel data to buffer */
dst = buffer;
for (i=0;i<height;i++) {
GLubyte *src = (GLubyte *) gl_pixel_addr_in_image( ctx, pixels, width,
height, format, srctype, GL_FALSE, i, 0 );
if (!src) {
free(buffer);
return NULL;
}
if (interleave) {
GLint j, k;
for (j=0;j<width;j++) {
for (k=0;k<components;k++) {
dst[k*width+j] = src[j*components+k];
}
}
}
else {
MEMCPY( dst, src, width_in_bytes );
}
dst += width_in_bytes;
}
if (ctx->Unpack.LsbFirst) {
gl_flip_bytes( buffer, height * width_in_bytes );
}
image = (struct gl_image *) malloc( sizeof(struct gl_image) );
if (image) {
image->Width = width;
image->Height = height;
image->Components = components;
image->Type = GL_UNSIGNED_BYTE;
image->Interleaved = interleave;
image->Data = buffer;
}
else {
free( buffer );
return NULL;
}
return image;
}
else if (desttype==GL_FLOAT) {
struct gl_image *image;
GLfloat *buffer, *dst;
GLenum format;
GLint elems_per_row;
GLint i, j;
elems_per_row = width * components;
buffer = (GLfloat *) malloc( height * elems_per_row * sizeof(GLfloat) );
if (!buffer) {
return NULL;
}
switch (components) {
case 1: format = GL_LUMINANCE; break;
case 2: format = GL_LUMINANCE_ALPHA; break;
case 3: format = GL_RGB; break;
case 4: format = GL_RGBA; break;
default: abort();
}
dst = buffer;
for (i=0;i<height;i++) {
GLvoid *src = gl_pixel_addr_in_image( ctx, pixels, width, height,
format, srctype, GL_FALSE,
i, 0 );
if (!src) {
free(buffer);
return NULL;
}
switch (srctype) {
case GL_UNSIGNED_BYTE:
for (j=0;j<elems_per_row;j++) {
*dst++ = (GLfloat) ((GLubyte*)src)[j];
}
break;
case GL_BYTE:
for (j=0;j<elems_per_row;j++) {
*dst++ = (GLfloat) ((GLbyte*)src)[j];
}
break;
case GL_UNSIGNED_SHORT:
if (ctx->Unpack.SwapBytes) {
for (j=0;j<elems_per_row;j++) {
GLushort value = ((GLushort*)src)[j];
value = ((value >> 8) & 0xff) | ((value&0xff) << 8);
*dst++ = (GLfloat) value;
}
}
else {
for (j=0;j<elems_per_row;j++) {
*dst++ = (GLfloat) ((GLushort*)src)[j];
}
}
break;
case GL_SHORT:
if (ctx->Unpack.SwapBytes) {
for (j=0;j<elems_per_row;j++) {
GLshort value = ((GLshort*)src)[j];
value = ((value >> 8) & 0xff) | ((value&0xff) << 8);
*dst++ = (GLfloat) value;
}
}
else {
for (j=0;j<elems_per_row;j++) {
*dst++ = (GLfloat) ((GLshort*)src)[j];
}
}
break;
case GL_UNSIGNED_INT:
if (ctx->Unpack.SwapBytes) {
GLuint value;
for (j=0;j<elems_per_row;j++) {
value = ((GLuint*)src)[j];
value = ((value & 0xff000000) >> 24)
| ((value & 0x00ff0000) >> 8)
| ((value & 0x0000ff00) << 8)
| ((value & 0x000000ff) << 24);
*dst++ = (GLfloat) value;
}
}
else {
for (j=0;j<elems_per_row;j++) {
*dst++ = (GLfloat) ((GLuint*)src)[j];
}
}
break;
case GL_INT:
if (ctx->Unpack.SwapBytes) {
GLint value;
for (j=0;j<elems_per_row;j++) {
value = ((GLint*)src)[j];
value = ((value & 0xff000000) >> 24)
| ((value & 0x00ff0000) >> 8)
| ((value & 0x0000ff00) << 8)
| ((value & 0x000000ff) << 24);
*dst++ = (GLfloat) value;
}
}
else {
for (j=0;j<elems_per_row;j++) {
*dst++ = (GLfloat) ((GLint*)src)[j];
}
}
break;
case GL_FLOAT:
if (ctx->Unpack.SwapBytes) {
GLint value;
for (j=0;j<elems_per_row;j++) {
value = ((GLuint*)src)[j];
value = ((value & 0xff000000) >> 24)
| ((value & 0x00ff0000) >> 8)
| ((value & 0x0000ff00) << 8)
| ((value & 0x000000ff) << 24);
*dst++ = *((GLfloat*) &value);
}
}
else {
MEMCPY( dst, src, elems_per_row*sizeof(GLfloat) );
dst += elems_per_row;
}
break;
default:
abort();
} /*switch*/
} /*for*/
image = (struct gl_image *) malloc( sizeof(struct gl_image) );
if (image) {
image->Width = width;
image->Height = height;
image->Components = components;
image->Type = GL_FLOAT;
image->Interleaved = GL_FALSE;
image->Data = buffer;
}
else {
free( buffer );
return NULL;
}
return image;
}
else {
abort();
}
return NULL; /* never get here */
}
void gl_free_image( struct gl_image *image )
{
if (image->Data) {
free(image->Data);
}
free(image);
}
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