engine/src/Utils/TgaLoader.cpp
2013-05-28 15:17:21 +00:00

246 lines
7.9 KiB
C++

#include "include/Utils/TgaLoader.h"
#include "include/Utils/Utils.h"
#include "include/TextureManager/SalmonTexture.h"
//Thanks to NeHe
namespace SE
{
unsigned char uTGAcompare[12] = {0,0,2, 0,0,0,0,0,0,0,0,0}; // Uncompressed TGA Header
unsigned char cTGAcompare[12] = {0,0,10,0,0,0,0,0,0,0,0,0}; // Compressed TGA Header
//bool LoadTGA(Texture * texture, char * filename) // Load a TGA file
bool LoadTGA(const std::string& filename, TTextureData& texture) // Load a TGA file
{
cardinal byteCount;
boost::shared_array<char> fTGA = CreateMemFromFile<char>(filename, byteCount);
TGAHeader tgaheader;
tgaheader = *(reinterpret_cast<TGAHeader*>(&fTGA[0]));
if(memcmp(uTGAcompare, &tgaheader, sizeof(tgaheader)) == 0) // See if header matches the predefined header of
{ // an Uncompressed TGA image
return LoadUncompressedTGA(texture, fTGA); // If so, jump to Uncompressed TGA loading code
}
else if(memcmp(cTGAcompare, &tgaheader, sizeof(tgaheader)) == 0) // See if header matches the predefined header of
{ // an RLE compressed TGA image
return LoadCompressedTGA(texture, fTGA); // If so, jump to Compressed TGA loading code
}
else // If header matches neither type
{
return false; // Exit function
}
// All went well, continue on
}
//bool LoadUncompressedTGA(Texture * texture, char * filename, FILE * fTGA) // Load an uncompressed TGA (note, much of this code is based on NeHe's
bool LoadUncompressedTGA(TTextureData& texture, boost::shared_array<char> fTGA) // Load an uncompressed TGA (note, much of this code is based on NeHe's
{ // TGA Loading code nehe.gamedev.net)
TGA tga;
int shift = sizeof(TGAHeader);
memcpy(tga.header, &fTGA[shift], CONST_TGA_INNER_HEADER_SIZE);
shift += CONST_TGA_INNER_HEADER_SIZE;
texture.Width = tga.header[1] * 256 + tga.header[0]; // Determine The TGA Width (highbyte*256+lowbyte)
texture.Height = tga.header[3] * 256 + tga.header[2]; // Determine The TGA Height (highbyte*256+lowbyte)
int bitsPerPixel = tga.header[4];
if (bitsPerPixel == 24)
{
strcpy(texture.Format, "bmp24");
}
else if (bitsPerPixel == 32)
{
strcpy(texture.Format, "bmp32");
}
else
{
return false;
}
//texture->bpp = tga.header[4]; // Determine the bits per pixel
tga.Width = texture.Width; // Copy width into local structure
tga.Height = texture.Height; // Copy height into local structure
tga.Bpp = bitsPerPixel; // Copy BPP into local structure
if((texture.Width <= 0) || (texture.Height <= 0)) // Make sure all information is valid
{
return false; // Return failed
}
tga.bytesPerPixel = (tga.Bpp / 8); // Compute the number of BYTES per pixel
tga.imageSize = (tga.bytesPerPixel * tga.Width * tga.Height); // Compute the total amout ofmemory needed to store data
texture.DataSize = tga.imageSize;
texture.Data = boost::shared_array<char>(new char [texture.DataSize]);
memcpy(&texture.Data[0], &fTGA[shift], texture.DataSize);
// Byte Swapping Optimized By Steve Thomas
for(unsigned int cswap = 0; cswap < (int)tga.imageSize; cswap += tga.bytesPerPixel)
{
texture.Data[cswap] ^= texture.Data[cswap+2] ^=
texture.Data[cswap] ^= texture.Data[cswap+2];
}
return true;
}
//bool LoadCompressedTGA(Texture * texture, char * filename, FILE * fTGA) // Load COMPRESSED TGAs
bool LoadCompressedTGA(TTextureData& texture, boost::shared_array<char> fTGA) // Load COMPRESSED TGAs
{
TGA tga;
int shift = sizeof(TGAHeader);
memcpy(tga.header, &fTGA[shift], CONST_TGA_INNER_HEADER_SIZE);
shift += CONST_TGA_INNER_HEADER_SIZE;
texture.Width = tga.header[1] * 256 + tga.header[0]; // Determine The TGA Width (highbyte*256+lowbyte)
texture.Height = tga.header[3] * 256 + tga.header[2]; // Determine The TGA Height (highbyte*256+lowbyte)
int bitsPerPixel = tga.header[4];
if (bitsPerPixel == 24)
{
strcpy(texture.Format, "bmp24");
}
else if (bitsPerPixel == 32)
{
strcpy(texture.Format, "bmp32");
}
else
{
return false;
}
tga.Width = texture.Width; // Copy width into local structure
tga.Height = texture.Height; // Copy height into local structure
tga.Bpp = bitsPerPixel; // Copy BPP into local structure
if((texture.Width <= 0) || (texture.Height <= 0)) //Make sure all texture info is ok
{
return false; // Return failed
}
tga.bytesPerPixel = (tga.Bpp / 8); // Compute BYTES per pixel
tga.imageSize = (tga.bytesPerPixel * tga.Width * tga.Height); // Compute amout of memory needed to store image
texture.DataSize = tga.imageSize;
texture.Data = boost::shared_array<char>(new char [texture.DataSize]);
unsigned int pixelcount = tga.Height * tga.Width; // Nuber of pixels in the image
unsigned int currentpixel = 0; // Current pixel being read
unsigned int currentbyte = 0; // Current byte
//GLubyte* colorbuffer = (GLubyte *)malloc(tga.bytesPerPixel); // Storage for 1 pixel
boost::shared_array<unsigned char> colorbuffer(new unsigned char[tga.bytesPerPixel]);
do
{
unsigned char chunkheader = 0; // Storage for "chunk" header
chunkheader = static_cast<unsigned char>(fTGA[shift]);
shift += sizeof(unsigned char);
if(chunkheader < 128) // If the ehader is < 128, it means the that is the number of RAW color packets minus 1
{ // that follow the header
chunkheader++; // add 1 to get number of following color values
for(short counter = 0; counter < chunkheader; counter++) // Read RAW color values
{
memcpy(&colorbuffer[0], &fTGA[shift], tga.bytesPerPixel);
shift += tga.bytesPerPixel;
texture.Data[currentbyte] = static_cast<char>(colorbuffer[2]);
texture.Data[currentbyte + 1] = static_cast<char>(colorbuffer[1]);
texture.Data[currentbyte + 2] = static_cast<char>(colorbuffer[0]);
if(tga.bytesPerPixel == 4) // if its a 32 bpp image
{
texture.Data[currentbyte + 3] = static_cast<char>(colorbuffer[3]);
}
currentbyte += tga.bytesPerPixel; // Increase thecurrent byte by the number of bytes per pixel
currentpixel++; // Increase current pixel by 1
if(currentpixel > pixelcount) // Make sure we havent read too many pixels
{
return false; // Return failed
}
}
}
else // chunkheader > 128 RLE data, next color reapeated chunkheader - 127 times
{
chunkheader -= 127; // Subteact 127 to get rid of the ID bit
memcpy(&colorbuffer[0], &fTGA[shift], tga.bytesPerPixel);
shift += tga.bytesPerPixel;
for(short counter = 0; counter < chunkheader; counter++) // copy the color into the image data as many times as dictated
{ // by the header
texture.Data[currentbyte] = static_cast<char>(colorbuffer[2]);
texture.Data[currentbyte + 1] = static_cast<char>(colorbuffer[1]);
texture.Data[currentbyte + 2] = static_cast<char>(colorbuffer[0]);
if(tga.bytesPerPixel == 4) // if its a 32 bpp image
{
texture.Data[currentbyte + 3] = static_cast<char>(colorbuffer[3]);
}
currentbyte += tga.bytesPerPixel; // Increase current byte by the number of bytes per pixel
currentpixel++; // Increase pixel count by 1
if(currentpixel > pixelcount) // Make sure we havent written too many pixels
{
return false; // Return failed
}
}
}
} while(currentpixel < pixelcount); // Loop while there are still pixels left
return true; // return success
}
} //namespace SE