2023-11-05 22:30:52 +03:00

275 lines
8.4 KiB
C++

#include "png.h"
#include <iostream>
#include <GL/glew.h>
#include "../graphics/Texture.h"
#ifndef _WIN32
#define LIBPNG
#endif
#ifdef LIBPNG
#include <png.h>
int _png_load(const char* file, int* width, int* height){
FILE *f;
int is_png, bit_depth, color_type, row_bytes;
png_infop info_ptr, end_info;
png_uint_32 t_width, t_height;
png_byte header[8], *image_data;
png_bytepp row_pointers;
png_structp png_ptr;
GLuint texture;
GLuint texturems;
int alpha;
if ( !( f = fopen(file, "r" ) ) ) {
return 0;
}
fread( header, 1, 8, f );
is_png = !png_sig_cmp( header, 0, 8 );
if ( !is_png ) {
fclose( f );
return 0;
}
png_ptr = png_create_read_struct( PNG_LIBPNG_VER_STRING, NULL,
NULL, NULL );
if ( !png_ptr ) {
fclose( f );
return 0;
}
info_ptr = png_create_info_struct( png_ptr );
if ( !info_ptr ) {
png_destroy_read_struct( &png_ptr, (png_infopp) NULL,
(png_infopp) NULL );
fclose( f );
return 0;
}
end_info = png_create_info_struct( png_ptr );
if ( !end_info ) {
png_destroy_read_struct( &png_ptr, (png_infopp) NULL,
(png_infopp) NULL );
fclose( f );
return 0;
}
if ( setjmp( png_jmpbuf( png_ptr ) ) ) {
png_destroy_read_struct( &png_ptr, &info_ptr, &end_info );
fclose( f );
return 0;
}
png_init_io( png_ptr, f );
png_set_sig_bytes( png_ptr, 8 );
png_read_info( png_ptr, info_ptr );
png_get_IHDR( png_ptr, info_ptr, &t_width, &t_height, &bit_depth,
&color_type, NULL, NULL, NULL );
*width = t_width;
*height = t_height;
png_read_update_info( png_ptr, info_ptr );
row_bytes = png_get_rowbytes( png_ptr, info_ptr );
image_data = (png_bytep) malloc( row_bytes * t_height * sizeof(png_byte) );
if ( !image_data ) {
png_destroy_read_struct( &png_ptr, &info_ptr, &end_info );
fclose( f );
return 0;
}
row_pointers = (png_bytepp) malloc( t_height * sizeof(png_bytep) );
if ( !row_pointers ) {
png_destroy_read_struct( &png_ptr, &info_ptr, &end_info );
free( image_data );
fclose( f );
return 0;
}
for (unsigned int i = 0; i < t_height; ++i ) {
row_pointers[t_height - 1 - i] = image_data + i * row_bytes;
}
png_read_image( png_ptr, row_pointers );
switch ( png_get_color_type( png_ptr, info_ptr ) ) {
case PNG_COLOR_TYPE_RGBA:
alpha = GL_RGBA;
break;
case PNG_COLOR_TYPE_RGB:
alpha = GL_RGB;
break;
default:
printf( "Color type %d not supported!\n",
png_get_color_type( png_ptr, info_ptr ) );
png_destroy_read_struct( &png_ptr, &info_ptr, &end_info );
return 0;
}
// configure second post-processing framebuffer
unsigned int framebuffer;
glGenFramebuffers(1, &framebuffer);
glBindFramebuffer(GL_FRAMEBUFFER, framebuffer);
glGenTextures(1, &texture);
glBindTexture(GL_TEXTURE_2D, texture);
glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, t_width, t_height, 0,
alpha, GL_UNSIGNED_BYTE, (GLvoid *) image_data);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAX_LEVEL, 3);
glGenerateMipmap(GL_TEXTURE_2D);
// glFramebufferTexture2D(GL_READ_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D, texture, 0); // we only need a color buffer
glBindTexture(GL_TEXTURE_2D, 0);
glBindFramebuffer(GL_FRAMEBUFFER, 0);
unsigned int framebufferms;
glGenFramebuffers(1, &framebufferms);
glBindFramebuffer(GL_FRAMEBUFFER, framebufferms);
// create a multisampled color attachment texture
glGenTextures(1, &texturems);
glBindTexture(GL_TEXTURE_2D_MULTISAMPLE, texturems);
glTexImage2DMultisample(GL_TEXTURE_2D_MULTISAMPLE, 16, GL_RGBA, t_width, t_height, GL_TRUE);
glFramebufferTexture2D(GL_DRAW_FRAMEBUFFER, GL_COLOR_ATTACHMENT0, GL_TEXTURE_2D_MULTISAMPLE, texturems, 0);
glTexParameteri(GL_TEXTURE_2D_MULTISAMPLE, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D_MULTISAMPLE, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D_MULTISAMPLE, GL_TEXTURE_WRAP_S, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D_MULTISAMPLE, GL_TEXTURE_WRAP_T, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D_MULTISAMPLE, GL_TEXTURE_MAX_LEVEL, 3);
// glGenerateMipmap(GL_TEXTURE_2D_MULTISAMPLE);
glBindFramebuffer(GL_READ_FRAMEBUFFER, framebuffer);
glBindFramebuffer(GL_DRAW_FRAMEBUFFER, framebufferms);
glBlitFramebuffer(0, 0, t_width, t_height, 0, 0, t_width, t_height, GL_COLOR_BUFFER_BIT, GL_NEAREST);
glBindTexture(GL_TEXTURE_2D_MULTISAMPLE, 0);
glBindFramebuffer(GL_FRAMEBUFFER, 0);
png_destroy_read_struct( &png_ptr, &info_ptr, &end_info );
free( image_data );
free( row_pointers );
fclose( f );
return texture;
}
#else
#include <spng.h>
#include <stdio.h>
#include <inttypes.h>
int _png_load(const char* file, int* pwidth, int* pheight){
int r = 0;
FILE *png;
char *pngbuf = nullptr;
spng_ctx *ctx = nullptr;
unsigned char *out = nullptr;
png = fopen(file, "rb");
if (png == nullptr){
std::cerr << "could not to open file " << file << std::endl;
return 0;
}
fseek(png, 0, SEEK_END);
long siz_pngbuf = ftell(png);
rewind(png);
if(siz_pngbuf < 1) {
std::cerr << "could not to read file " << file << std::endl;
return 0;
}
pngbuf = new char[siz_pngbuf];
if(fread(pngbuf, siz_pngbuf, 1, png) != 1){
std::cerr << "fread() failed" << std::endl;
return 0;
}
ctx = spng_ctx_new(0);
if (ctx == nullptr){
std::cerr << "spng_ctx_new() failed" << std::endl;
return 0;
}
r = spng_set_crc_action(ctx, SPNG_CRC_USE, SPNG_CRC_USE);
if (r){
std::cerr << "spng_set_crc_action() error: " << spng_strerror(r) << std::endl;
return 0;
}
r = spng_set_png_buffer(ctx, pngbuf, siz_pngbuf);
if (r){
std::cerr << "spng_set_png_buffer() error: " << spng_strerror(r) << std::endl;
return 0;
}
spng_ihdr ihdr;
r = spng_get_ihdr(ctx, &ihdr);
if (r){
std::cerr << "spng_get_ihdr() error: " << spng_strerror(r) << std::endl;
return 0;
}
char *clr_type_str;
if(ihdr.color_type == SPNG_COLOR_TYPE_GRAYSCALE)
clr_type_str = "grayscale";
else if(ihdr.color_type == SPNG_COLOR_TYPE_TRUECOLOR)
clr_type_str = "truecolor";
else if(ihdr.color_type == SPNG_COLOR_TYPE_INDEXED)
clr_type_str = "indexed color";
else if(ihdr.color_type == SPNG_COLOR_TYPE_GRAYSCALE_ALPHA)
clr_type_str = "grayscale with alpha";
else
clr_type_str = "truecolor with alpha";
size_t out_size;
r = spng_decoded_image_size(ctx, SPNG_FMT_RGBA8, &out_size);
if (r){
std::cerr << "spng_decoded_image_size() error: " << spng_strerror(r) << std::endl;
return 0;
}
out = new unsigned char[out_size];
r = spng_decode_image(ctx, out, out_size, SPNG_FMT_RGBA8, 0);
if (r){
std::cerr << "spng_decode_image() error: " << spng_strerror(r) << std::endl;
return 0;
}
unsigned char* flipped = new unsigned char[out_size];
for (size_t i = 0; i < ihdr.height; i+=1){
size_t rowsize = ihdr.width*4;
for (size_t j = 0; j < rowsize; j++){
flipped[(ihdr.height-i-1)*rowsize+j] = out[i*rowsize+j];
}
}
delete[] out;
unsigned int texture;
int alpha = GL_RGBA;
glGenTextures(1, &texture);
glBindTexture(GL_TEXTURE_2D, texture);
glPixelStorei(GL_UNPACK_ALIGNMENT, 1);
glTexImage2D(GL_TEXTURE_2D, 0, GL_RGBA, ihdr.width, ihdr.height, 0,
alpha, GL_UNSIGNED_BYTE, (GLvoid *) flipped);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_NEAREST);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_REPEAT);
glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
glBindTexture(GL_TEXTURE_2D, 0);
pwidth[0] = ihdr.width;
pheight[0] = ihdr.height;
spng_ctx_free(ctx);
delete[] pngbuf;
return texture;
}
#endif
Texture* png::load_texture(std::string filename){
int width, height;
GLuint texture = _png_load(filename.c_str(), &width, &height);
if (texture == 0){
std::cerr << "Could not load texture " << filename << std::endl;
return nullptr;
}
return new Texture(texture, width, height);
}