bullet3/examples/TinyRenderer/tgaimage.cpp
Erwin Coumans aa9a276a71 fix typo in texels flip
add support to create a cube in TinyRenderer (quick test)
2016-04-28 23:01:49 -07:00

357 lines
11 KiB
C++

#include <iostream>
#include <fstream>
#include <string.h>
#include <time.h>
#include <math.h>
#include "tgaimage.h"
TGAImage::TGAImage() : data(NULL), width(0), height(0), bytespp(0) {}
TGAImage::TGAImage(int w, int h, int bpp) : data(NULL), width(w), height(h), bytespp(bpp) {
unsigned long nbytes = width*height*bytespp;
data = new unsigned char[nbytes];
memset(data, 0, nbytes);
}
TGAImage::TGAImage(const TGAImage &img) : data(NULL), width(img.width), height(img.height), bytespp(img.bytespp) {
unsigned long nbytes = width*height*bytespp;
data = new unsigned char[nbytes];
memcpy(data, img.data, nbytes);
}
TGAImage::~TGAImage() {
if (data) delete [] data;
}
TGAImage & TGAImage::operator =(const TGAImage &img) {
if (this != &img) {
if (data) delete [] data;
width = img.width;
height = img.height;
bytespp = img.bytespp;
unsigned long nbytes = width*height*bytespp;
data = new unsigned char[nbytes];
memcpy(data, img.data, nbytes);
}
return *this;
}
bool TGAImage::read_tga_file(const char *filename) {
if (data) delete [] data;
data = NULL;
std::ifstream in;
in.open (filename, std::ios::binary);
if (!in.is_open()) {
std::cerr << "can't open file " << filename << "\n";
in.close();
return false;
}
TGA_Header header;
in.read((char *)&header, sizeof(header));
if (!in.good()) {
in.close();
std::cerr << "an error occured while reading the header\n";
return false;
}
width = header.width;
height = header.height;
bytespp = header.bitsperpixel>>3;
if (width<=0 || height<=0 || (bytespp!=GRAYSCALE && bytespp!=RGB && bytespp!=RGBA)) {
in.close();
std::cerr << "bad bpp (or width/height) value\n";
return false;
}
unsigned long nbytes = bytespp*width*height;
data = new unsigned char[nbytes];
if (3==header.datatypecode || 2==header.datatypecode) {
in.read((char *)data, nbytes);
if (!in.good()) {
in.close();
std::cerr << "an error occured while reading the data\n";
return false;
}
} else if (10==header.datatypecode||11==header.datatypecode) {
if (!load_rle_data(in)) {
in.close();
std::cerr << "an error occured while reading the data\n";
return false;
}
} else {
in.close();
std::cerr << "unknown file format " << (int)header.datatypecode << "\n";
return false;
}
if (!(header.imagedescriptor & 0x20)) {
flip_vertically();
}
if (header.imagedescriptor & 0x10) {
flip_horizontally();
}
std::cerr << width << "x" << height << "/" << bytespp*8 << "\n";
in.close();
return true;
}
bool TGAImage::load_rle_data(std::ifstream &in) {
unsigned long pixelcount = width*height;
unsigned long currentpixel = 0;
unsigned long currentbyte = 0;
TGAColor colorbuffer;
do {
unsigned char chunkheader = 0;
chunkheader = in.get();
if (!in.good()) {
std::cerr << "an error occured while reading the data\n";
return false;
}
if (chunkheader<128) {
chunkheader++;
for (int i=0; i<chunkheader; i++) {
in.read((char *)colorbuffer.bgra, bytespp);
if (!in.good()) {
std::cerr << "an error occured while reading the header\n";
return false;
}
for (int t=0; t<bytespp; t++)
data[currentbyte++] = colorbuffer.bgra[t];
currentpixel++;
if (currentpixel>pixelcount) {
std::cerr << "Too many pixels read\n";
return false;
}
}
} else {
chunkheader -= 127;
in.read((char *)colorbuffer.bgra, bytespp);
if (!in.good()) {
std::cerr << "an error occured while reading the header\n";
return false;
}
for (int i=0; i<chunkheader; i++) {
for (int t=0; t<bytespp; t++)
data[currentbyte++] = colorbuffer.bgra[t];
currentpixel++;
if (currentpixel>pixelcount) {
std::cerr << "Too many pixels read\n";
return false;
}
}
}
} while (currentpixel < pixelcount);
return true;
}
bool TGAImage::write_tga_file(const char *filename, bool rle) const {
unsigned char developer_area_ref[4] = {0, 0, 0, 0};
unsigned char extension_area_ref[4] = {0, 0, 0, 0};
unsigned char footer[18] = {'T','R','U','E','V','I','S','I','O','N','-','X','F','I','L','E','.','\0'};
std::ofstream out;
out.open (filename, std::ios::binary);
if (!out.is_open()) {
std::cerr << "can't open file " << filename << "\n";
out.close();
return false;
}
TGA_Header header;
memset((void *)&header, 0, sizeof(header));
header.bitsperpixel = bytespp<<3;
header.width = width;
header.height = height;
header.datatypecode = (bytespp==GRAYSCALE?(rle?11:3):(rle?10:2));
header.imagedescriptor = 0x20; // top-left origin
out.write((char *)&header, sizeof(header));
if (!out.good()) {
out.close();
std::cerr << "can't dump the tga file\n";
return false;
}
if (!rle) {
out.write((char *)data, width*height*bytespp);
if (!out.good()) {
std::cerr << "can't unload raw data\n";
out.close();
return false;
}
} else {
if (!unload_rle_data(out)) {
out.close();
std::cerr << "can't unload rle data\n";
return false;
}
}
out.write((char *)developer_area_ref, sizeof(developer_area_ref));
if (!out.good()) {
std::cerr << "can't dump the tga file\n";
out.close();
return false;
}
out.write((char *)extension_area_ref, sizeof(extension_area_ref));
if (!out.good()) {
std::cerr << "can't dump the tga file\n";
out.close();
return false;
}
out.write((char *)footer, sizeof(footer));
if (!out.good()) {
std::cerr << "can't dump the tga file\n";
out.close();
return false;
}
out.close();
return true;
}
// TODO: it is not necessary to break a raw chunk for two equal pixels (for the matter of the resulting size)
bool TGAImage::unload_rle_data(std::ofstream &out) const {
const unsigned char max_chunk_length = 128;
unsigned long npixels = width*height;
unsigned long curpix = 0;
while (curpix<npixels) {
unsigned long chunkstart = curpix*bytespp;
unsigned long curbyte = curpix*bytespp;
unsigned char run_length = 1;
bool raw = true;
while (curpix+run_length<npixels && run_length<max_chunk_length) {
bool succ_eq = true;
for (int t=0; succ_eq && t<bytespp; t++) {
succ_eq = (data[curbyte+t]==data[curbyte+t+bytespp]);
}
curbyte += bytespp;
if (1==run_length) {
raw = !succ_eq;
}
if (raw && succ_eq) {
run_length--;
break;
}
if (!raw && !succ_eq) {
break;
}
run_length++;
}
curpix += run_length;
out.put(raw?run_length-1:run_length+127);
if (!out.good()) {
std::cerr << "can't dump the tga file\n";
return false;
}
out.write((char *)(data+chunkstart), (raw?run_length*bytespp:bytespp));
if (!out.good()) {
std::cerr << "can't dump the tga file\n";
return false;
}
}
return true;
}
TGAColor TGAImage::get(int x, int y) const {
if (!data || x<0 || y<0 || x>=width || y>=height) {
return TGAColor(128.f,128.f,128.f,255.f);
}
return TGAColor(data+(x+y*width)*bytespp, bytespp);
}
bool TGAImage::set(int x, int y, TGAColor &c) {
if (!data || x<0 || y<0 || x>=width || y>=height) {
return false;
}
memcpy(data+(x+y*width)*bytespp, c.bgra, bytespp);
return true;
}
bool TGAImage::set(int x, int y, const TGAColor &c) {
if (!data || x<0 || y<0 || x>=width || y>=height) {
return false;
}
memcpy(data+(x+y*width)*bytespp, c.bgra, bytespp);
return true;
}
int TGAImage::get_bytespp() {
return bytespp;
}
int TGAImage::get_width() {
return width;
}
int TGAImage::get_height() {
return height;
}
bool TGAImage::flip_horizontally() {
if (!data) return false;
int half = width>>1;
for (int i=0; i<half; i++) {
for (int j=0; j<height; j++) {
TGAColor c1 = get(i, j);
TGAColor c2 = get(width-1-i, j);
set(i, j, c2);
set(width-1-i, j, c1);
}
}
return true;
}
bool TGAImage::flip_vertically() {
if (!data) return false;
unsigned long bytes_per_line = width*bytespp;
unsigned char *line = new unsigned char[bytes_per_line];
int half = height>>1;
for (int j=0; j<half; j++) {
unsigned long l1 = j*bytes_per_line;
unsigned long l2 = (height-1-j)*bytes_per_line;
memmove((void *)line, (void *)(data+l1), bytes_per_line);
memmove((void *)(data+l1), (void *)(data+l2), bytes_per_line);
memmove((void *)(data+l2), (void *)line, bytes_per_line);
}
delete [] line;
return true;
}
unsigned char *TGAImage::buffer() {
return data;
}
void TGAImage::clear() {
memset((void *)data, 0, width*height*bytespp);
}
bool TGAImage::scale(int w, int h) {
if (w<=0 || h<=0 || !data) return false;
unsigned char *tdata = new unsigned char[w*h*bytespp];
int nscanline = 0;
int oscanline = 0;
int erry = 0;
unsigned long nlinebytes = w*bytespp;
unsigned long olinebytes = width*bytespp;
for (int j=0; j<height; j++) {
int errx = width-w;
int nx = -bytespp;
int ox = -bytespp;
for (int i=0; i<width; i++) {
ox += bytespp;
errx += w;
while (errx>=(int)width) {
errx -= width;
nx += bytespp;
memcpy(tdata+nscanline+nx, data+oscanline+ox, bytespp);
}
}
erry += h;
oscanline += olinebytes;
while (erry>=(int)height) {
if (erry>=(int)height<<1) // it means we jump over a scanline
memcpy(tdata+nscanline+nlinebytes, tdata+nscanline, nlinebytes);
erry -= height;
nscanline += nlinebytes;
}
}
delete [] data;
data = tdata;
width = w;
height = h;
return true;
}