From 27a0e0e0a1d81b302acd70c4ddeb736af9283a03 Mon Sep 17 00:00:00 2001 From: Alexandre Moine Date: Fri, 26 Aug 2016 18:36:03 +0200 Subject: [PATCH] Add support for savepng.c --- Makefile.am | 6 +- configure.ac | 2 + savepng.c | 154 +++++++++++++++++++++++++++++++++++++++++++++++++++ 3 files changed, 161 insertions(+), 1 deletion(-) create mode 100644 savepng.c diff --git a/Makefile.am b/Makefile.am index 44349cb0..34e6e209 100644 --- a/Makefile.am +++ b/Makefile.am @@ -3,7 +3,7 @@ bin_PROGRAMS = hyperrogue hyperroguedir = $(datadir)/hyperrogue dist_hyperrogue_DATA = music/hyperrogue-music.txt DejaVuSans-Bold.ttf dist_doc_DATA = README.md -hyperrogue_SOURCES = hyper.cpp +hyperrogue_SOURCES = hyper.cpp savepng.c # Some definitions used in graph.cpp hyperrogue_CPPFLAGS = -DFONTDESTDIR=\"$(pkgdatadir)/DejaVuSans-Bold.ttf\" -DMUSICDESTDIR=\"$(pkgdatadir)/hyperrogue-music.txt\" -O2 @@ -26,6 +26,10 @@ langen_CXXFLAGS = -O0 language-data.cpp: langen ./langen > language-data.cpp +# Generation of savepng +#noinst_PROGRAMS += savepng +#savepng_SOURCES = savepng.c + # Local clean rules clean-local: rm -rf language-data.cpp diff --git a/configure.ac b/configure.ac index 2d9b4c48..6dd50fca 100644 --- a/configure.ac +++ b/configure.ac @@ -34,6 +34,8 @@ AC_CHECK_LIB([SDL_mixer], [main], [], AC_MSG_ERROR([SDL_mixer library was not fo AC_CHECK_LIB([SDL_gfx], [main], [], [AS_IF( test ["${host_os#*mingw}" != "$host_os"], [export wincppflags=$wincppflags" dll/SDL_gfx.dll" && AC_MSG_RESULT([Building for windows, ignoring])] ,AC_MSG_ERROR([SDL_gfx library was not found]))]) # FIXME: Replace `main' with a function in `-lSDL_ttf': AC_CHECK_LIB([SDL_ttf], [main], [], [AS_IF( test ["${host_os#*mingw}" != "$host_os"], [export wincppflags=$wincppflags" dll/SDL_ttf.dll" && AC_MSG_RESULT([Building for windows, ignoring])] ,AC_MSG_ERROR([SDL_ttf library was not found]))]) +# Test for libpng +AC_CHECK_LIB([png], [main], [], AC_MSG_ERROR([png library was not found])) # Checks for header files. AC_CHECK_HEADERS([stdlib.h unistd.h]) diff --git a/savepng.c b/savepng.c new file mode 100644 index 00000000..72a05de3 --- /dev/null +++ b/savepng.c @@ -0,0 +1,154 @@ +/* + * SDL_SavePNG -- libpng-based SDL_Surface writer. + * + * This code is free software, available under zlib/libpng license. + * http://www.libpng.org/pub/png/src/libpng-LICENSE.txt + */ +#include +#include + +#define SUCCESS 0 +#define ERROR -1 + +#define USE_ROW_POINTERS + +#if SDL_BYTEORDER == SDL_BIG_ENDIAN +#define rmask 0xFF000000 +#define gmask 0x00FF0000 +#define bmask 0x0000FF00 +#define amask 0x000000FF +#else +#define rmask 0x000000FF +#define gmask 0x0000FF00 +#define bmask 0x00FF0000 +#define amask 0xFF000000 +#endif + +/* libpng callbacks */ +static void png_error_SDL(png_structp ctx, png_const_charp str) +{ + SDL_SetError("libpng: %s\n", str); +} +static void png_write_SDL(png_structp png_ptr, png_bytep data, png_size_t length) +{ + SDL_RWops *rw = (SDL_RWops*)png_get_io_ptr(png_ptr); + SDL_RWwrite(rw, data, sizeof(png_byte), length); +} + +SDL_Surface *SDL_PNGFormatAlpha(SDL_Surface *src) +{ + SDL_Surface *surf; + SDL_Rect rect = { 0 }; + + /* NO-OP for images < 32bpp and 32bpp images that already have Alpha channel */ + if (src->format->BitsPerPixel <= 24 || src->format->Amask) { + src->refcount++; + return src; + } + + /* Convert 32bpp alpha-less image to 24bpp alpha-less image */ + rect.w = src->w; + rect.h = src->h; + surf = SDL_CreateRGBSurface(src->flags, src->w, src->h, 24, + src->format->Rmask, src->format->Gmask, src->format->Bmask, 0); + SDL_LowerBlit(src, &rect, surf, &rect); + + return surf; +} + +int SDL_SavePNG_RW(SDL_Surface *surface, SDL_RWops *dst, int freedst) +{ + png_structp png_ptr; + png_infop info_ptr; + png_colorp pal_ptr; + SDL_Palette *pal; + int i, colortype; +#ifdef USE_ROW_POINTERS + png_bytep *row_pointers; +#endif + /* Initialize and do basic error checking */ + if (!dst) + { + SDL_SetError("Argument 2 to SDL_SavePNG_RW can't be NULL, expecting SDL_RWops*\n"); + return (ERROR); + } + if (!surface) + { + SDL_SetError("Argument 1 to SDL_SavePNG_RW can't be NULL, expecting SDL_Surface*\n"); + if (freedst) SDL_RWclose(dst); + return (ERROR); + } + png_ptr = png_create_write_struct(PNG_LIBPNG_VER_STRING, NULL, png_error_SDL, NULL); /* err_ptr, err_fn, warn_fn */ + if (!png_ptr) + { + SDL_SetError("Unable to png_create_write_struct on %s\n", PNG_LIBPNG_VER_STRING); + if (freedst) SDL_RWclose(dst); + return (ERROR); + } + info_ptr = png_create_info_struct(png_ptr); + if (!info_ptr) + { + SDL_SetError("Unable to png_create_info_struct\n"); + png_destroy_write_struct(&png_ptr, NULL); + if (freedst) SDL_RWclose(dst); + return (ERROR); + } + if (setjmp(png_jmpbuf(png_ptr))) /* All other errors, see also "png_error_SDL" */ + { + png_destroy_write_struct(&png_ptr, &info_ptr); + if (freedst) SDL_RWclose(dst); + return (ERROR); + } + + /* Setup our RWops writer */ + png_set_write_fn(png_ptr, dst, png_write_SDL, NULL); /* w_ptr, write_fn, flush_fn */ + + /* Prepare chunks */ + colortype = PNG_COLOR_MASK_COLOR; + if (surface->format->BytesPerPixel > 0 + && surface->format->BytesPerPixel <= 8 + && (pal = surface->format->palette)) + { + colortype |= PNG_COLOR_MASK_PALETTE; + pal_ptr = (png_colorp)malloc(pal->ncolors * sizeof(png_color)); + for (i = 0; i < pal->ncolors; i++) { + pal_ptr[i].red = pal->colors[i].r; + pal_ptr[i].green = pal->colors[i].g; + pal_ptr[i].blue = pal->colors[i].b; + } + png_set_PLTE(png_ptr, info_ptr, pal_ptr, pal->ncolors); + free(pal_ptr); + } + else if (surface->format->BytesPerPixel > 3 || surface->format->Amask) + colortype |= PNG_COLOR_MASK_ALPHA; + + png_set_IHDR(png_ptr, info_ptr, surface->w, surface->h, 8, colortype, + PNG_INTERLACE_NONE, PNG_COMPRESSION_TYPE_DEFAULT, PNG_FILTER_TYPE_DEFAULT); + +// png_set_packing(png_ptr); + + /* Allow BGR surfaces */ + if (surface->format->Rmask == bmask + && surface->format->Gmask == gmask + && surface->format->Bmask == rmask) + png_set_bgr(png_ptr); + + /* Write everything */ + png_write_info(png_ptr, info_ptr); +#ifdef USE_ROW_POINTERS + row_pointers = (png_bytep*) malloc(sizeof(png_bytep)*surface->h); + for (i = 0; i < surface->h; i++) + row_pointers[i] = (png_bytep)(Uint8*)surface->pixels + i * surface->pitch; + png_write_image(png_ptr, row_pointers); + free(row_pointers); +#else + for (i = 0; i < surface->h; i++) + png_write_row(png_ptr, (png_bytep)(Uint8*)surface->pixels + i * surface->pitch); +#endif + png_write_end(png_ptr, info_ptr); + + /* Done */ + png_destroy_write_struct(&png_ptr, &info_ptr); + if (freedst) SDL_RWclose(dst); + return (SUCCESS); +}