GLUSboolean GLUSAPIENTRY glusLoadTgaImage(const GLUSchar* filename, GLUStgaimage* tgaimage)
{
FILE* file;
GLUSubyte type;
GLUSubyte bitsPerPixel;
size_t elementsRead;
// check, if we have a valid pointer
if (!filename || !tgaimage)
{
return GLUS_FALSE;
}
tgaimage->width = 0;
tgaimage->height = 0;
tgaimage->depth = 0;
tgaimage->data = 0;
tgaimage->format = 0;
// open filename in "read binary" mode
file = fopen(filename, "rb");
if (!file)
{
return GLUS_FALSE;
}
// seek through the tga header, up to the type:
if(fseek(file, 2, SEEK_CUR))
{
fclose(file);
return GLUS_FALSE;
}
// read the type
elementsRead = fread(&type, 1, 1, file);
if (!glusCheckFileRead(file, elementsRead, 1))
{
return GLUS_FALSE;
}
// check the type
if (type != 2 && type != 10 && type != 11)
{
fclose(file);
return GLUS_FALSE;
}
// seek through the tga header, up to the width/height:
if(fseek(file, 9, SEEK_CUR))
{
fclose(file);
return GLUS_FALSE;
}
// read the width
elementsRead = fread(&tgaimage->width, 2, 1, file);
if (!glusCheckFileRead(file, elementsRead, 1))
{
glusDestroyTgaImage(tgaimage);
return GLUS_FALSE;
}
if (tgaimage->width > GLUS_MAX_DIMENSION)
{
glusDestroyTgaImage(tgaimage);
return GLUS_FALSE;
}
// read the height
elementsRead = fread(&tgaimage->height, 2, 1, file);
if (!glusCheckFileRead(file, elementsRead, 1))
{
glusDestroyTgaImage(tgaimage);
return GLUS_FALSE;
}
if (tgaimage->height > GLUS_MAX_DIMENSION)
{
glusDestroyTgaImage(tgaimage);
return GLUS_FALSE;
}
tgaimage->depth = 1;
// read the bits per pixel
elementsRead = fread(&bitsPerPixel, 1, 1, file);
if (!glusCheckFileRead(file, elementsRead, 1))
{
glusDestroyTgaImage(tgaimage);
return GLUS_FALSE;
}
// check the pixel depth
if (bitsPerPixel != 8 && bitsPerPixel != 24 && bitsPerPixel != 32)
{
fclose(file);
return GLUS_FALSE;
}
else
{
tgaimage->format = GLUS_LUMINANCE;
if (bitsPerPixel == 24)
{
tgaimage->format = GLUS_RGB;
}
else if (bitsPerPixel == 32)
{
tgaimage->format = GLUS_RGBA;
}
}
// move file pointer to beginning of targa data
if(fseek(file, 1, SEEK_CUR))
{
fclose(file);
glusDestroyTgaImage(tgaimage);
return GLUS_FALSE;
}
// allocate enough memory for the targa data
tgaimage->data = (GLUSubyte*) malloc((size_t)tgaimage->width * tgaimage->height * bitsPerPixel / 8);
// verify memory allocation
if (!tgaimage->data)
{
fclose(file);
glusDestroyTgaImage(tgaimage);
return GLUS_FALSE;
}
if (type == 2)
{
// read in the raw data
elementsRead = fread(tgaimage->data, 1, (size_t)tgaimage->width * tgaimage->height * bitsPerPixel / 8, file);
if (!glusCheckFileRead(file, elementsRead, (size_t)tgaimage->width * tgaimage->height * bitsPerPixel / 8))
{
glusDestroyTgaImage(tgaimage);
return GLUS_FALSE;
}
}
else
{
// RLE encoded
GLUSint pixelsRead = 0;
while (pixelsRead < tgaimage->width * tgaimage->height)
{
GLUSubyte amount;
elementsRead = fread(&amount, 1, 1, file);
if (!glusCheckFileRead(file, elementsRead, 1))
{
glusDestroyTgaImage(tgaimage);
return GLUS_FALSE;
}
if (amount & 0x80)
{
GLUSint i;
GLUSint k;
amount &= 0x7F;
amount++;
// read in the rle data
elementsRead = fread(&tgaimage->data[pixelsRead * bitsPerPixel / 8], 1, bitsPerPixel / 8, file);
if (!glusCheckFileRead(file, elementsRead, bitsPerPixel / 8))
{
glusDestroyTgaImage(tgaimage);
return GLUS_FALSE;
}
for (i = 1; i < amount; i++)
{
for (k = 0; k < bitsPerPixel / 8; k++)
{
tgaimage->data[(pixelsRead + i) * bitsPerPixel / 8 + k] = tgaimage->data[pixelsRead * bitsPerPixel / 8 + k];
}
}
}
else
{
amount &= 0x7F;
amount++;
// read in the raw data
elementsRead = fread(&tgaimage->data[pixelsRead * bitsPerPixel / 8], 1, (size_t) amount * bitsPerPixel / 8, file);
if (!glusCheckFileRead(file, elementsRead, (size_t) amount * bitsPerPixel / 8))
{
glusDestroyTgaImage(tgaimage);
return GLUS_FALSE;
}
}
pixelsRead += amount;
}
}
// swap the color if necessary
if (bitsPerPixel == 24 || bitsPerPixel == 32)
{
glusSwapColorChannel(tgaimage->width, tgaimage->height, tgaimage->format, tgaimage->data);
}
// close the file
fclose(file);
return GLUS_TRUE;
}
GLUSboolean GLUSAPIENTRY glusSaveTgaImage(const GLUSchar* filename, const GLUStgaimage* tgaimage)
{
FILE* file;
GLUSubyte buffer[12];
GLUSubyte bitsPerPixel;
size_t elementsWritten;
GLUSubyte* data;
// check, if we have a valid pointer
if (!filename || !tgaimage)
{
return GLUS_FALSE;
}
// open filename in "write binary" mode
file = fopen(filename, "wb");
if (!file)
{
return GLUS_FALSE;
}
switch (tgaimage->format)
{
case GLUS_ALPHA:
case GLUS_LUMINANCE:
bitsPerPixel = 8;
break;
case GLUS_RGB:
bitsPerPixel = 24;
break;
case GLUS_RGBA:
bitsPerPixel = 32;
break;
default:
fclose(file);
return GLUS_FALSE;
}
if (bitsPerPixel == 8)
{
buffer[2] = 3;
}
else
{
buffer[2] = 2;
}
// TGA header
buffer[0] = 0;
buffer[1] = 0;
buffer[3] = 0;
buffer[4] = 0;
buffer[5] = 0;
buffer[6] = 0;
buffer[7] = 0;
buffer[8] = 0;
buffer[9] = 0;
buffer[10] = 0;
buffer[11] = 0;
elementsWritten = fwrite(buffer, 1, 12, file);
if (!glusCheckFileWrite(file, elementsWritten, 12))
{
return GLUS_FALSE;
}
elementsWritten = fwrite(&tgaimage->width, 1, sizeof(tgaimage->width), file);
if (!glusCheckFileWrite(file, elementsWritten, 2))
{
return GLUS_FALSE;
}
elementsWritten = fwrite(&tgaimage->height, 1, sizeof(tgaimage->height), file);
if (!glusCheckFileWrite(file, elementsWritten, 2))
{
return GLUS_FALSE;
}
elementsWritten = fwrite(&bitsPerPixel, 1, sizeof(bitsPerPixel), file);
if (!glusCheckFileWrite(file, elementsWritten, 1))
{
return GLUS_FALSE;
}
buffer[0] = 0;
elementsWritten = fwrite(buffer, 1, 1, file);
if (!glusCheckFileWrite(file, elementsWritten, 1))
{
return GLUS_FALSE;
}
data = malloc(tgaimage->width * tgaimage->height * bitsPerPixel / 8);
if (!data)
{
fclose(file);
return GLUS_FALSE;
}
memcpy(data, tgaimage->data, tgaimage->width * tgaimage->height * bitsPerPixel / 8);
if (bitsPerPixel >= 24)
{
glusSwapColorChannel(tgaimage->width, tgaimage->height, tgaimage->format, data);
}
elementsWritten = fwrite(data, 1, tgaimage->width * tgaimage->height * bitsPerPixel / 8, file);
free(data);
if (!glusCheckFileWrite(file, elementsWritten, tgaimage->width * tgaimage->height * bitsPerPixel / 8))
{
return GLUS_FALSE;
}
fclose(file);
return GLUS_TRUE;
}
