From a418aa7dd5e94cbf1ab2a6fa1c63f60e5e087d42 Mon Sep 17 00:00:00 2001 From: Doug Zongker Date: Mon, 17 Mar 2014 12:10:02 -0700 Subject: refactor image resource loading code in minui Reduce the number of copies of libpng boilerplate. Rename res_create_* functions to be more clear. Make explicit the use of the framebuffer pixel format for images, and handle more combinations of input and output (eg, loading a grayscale image for display rather than use as a text alpha channel). Change-Id: I3d41c800a8f4c22b2f0167967ce6ee4d6b2b8846 --- minui/graphics.c | 2 +- minui/minui.h | 38 ++++- minui/resources.c | 440 +++++++++++++++++++++++++----------------------------- 3 files changed, 242 insertions(+), 238 deletions(-) (limited to 'minui') diff --git a/minui/graphics.c b/minui/graphics.c index f8ffa89..32b3361 100644 --- a/minui/graphics.c +++ b/minui/graphics.c @@ -269,7 +269,7 @@ static void gr_init_font(void) { gr_font = calloc(sizeof(*gr_font), 1); - int res = res_create_surface("font", &(gr_font->texture)); + int res = res_create_alpha_surface("font", &(gr_font->texture)); if (res == 0) { // The font image should be a 96x2 array of character images. The // columns are the printable ASCII characters 0x20 - 0x7f. The diff --git a/minui/minui.h b/minui/minui.h index 328da1e..d8d53fa 100644 --- a/minui/minui.h +++ b/minui/minui.h @@ -80,10 +80,40 @@ void ev_dispatch(void); // Resources -// Returns 0 if no error, else negative. -int res_create_surface(const char* name, gr_surface* pSurface); -int res_create_multi_surface(const char* name, int* frames, gr_surface** pSurface); -int res_create_localized_surface(const char* name, gr_surface* pSurface); +// res_create_*_surface() functions return 0 if no error, else +// negative. +// +// A "display" surface is one that is intended to be drawn to the +// screen with gr_blit(). An "alpha" surface is a grayscale image +// interpreted as an alpha mask used to render text in the current +// color (with gr_text() or gr_texticon()). +// +// All these functions load PNG images from "/res/images/${name}.png". + +// Load a single display surface from a PNG image. +int res_create_display_surface(const char* name, gr_surface* pSurface); + +// Load an array of display surfaces from a single PNG image. The PNG +// should have a 'Frames' text chunk whose value is the number of +// frames this image represents. The pixel data itself is interlaced +// by row. +int res_create_multi_display_surface(const char* name, + int* frames, gr_surface** pSurface); + +// Load a single alpha surface from a grayscale PNG image. +int res_create_alpha_surface(const char* name, gr_surface* pSurface); + +// Load part of a grayscale PNG image that is the first match for the +// given locale. The image is expected to be a composite of multiple +// translations of the same text, with special added rows that encode +// the subimages' size and intended locale in the pixel data. See +// development/tools/recovery_l10n for an app that will generate these +// specialized images from Android resources. +int res_create_localized_alpha_surface(const char* name, const char* locale, + gr_surface* pSurface); + +// Free a surface allocated by any of the res_create_*_surface() +// functions. void res_free_surface(gr_surface surface); #ifdef __cplusplus diff --git a/minui/resources.c b/minui/resources.c index a6528b3..69fd14b 100644 --- a/minui/resources.c +++ b/minui/resources.c @@ -44,15 +44,11 @@ static gr_surface malloc_surface(size_t data_size) { return surface; } -int res_create_surface(const char* name, gr_surface* pSurface) { +static int open_png(const char* name, png_structp* png_ptr, png_infop* info_ptr, + png_uint_32* width, png_uint_32* height, png_byte* channels) { char resPath[256]; - gr_surface surface = NULL; - int result = 0; unsigned char header[8]; - png_structp png_ptr = NULL; - png_infop info_ptr = NULL; - - *pSurface = NULL; + int result = 0; snprintf(resPath, sizeof(resPath)-1, "/res/images/%s.png", name); resPath[sizeof(resPath)-1] = '\0'; @@ -73,170 +69,182 @@ int res_create_surface(const char* name, gr_surface* pSurface) { goto exit; } - png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL); - if (!png_ptr) { + *png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL); + if (!*png_ptr) { result = -4; goto exit; } - info_ptr = png_create_info_struct(png_ptr); - if (!info_ptr) { + *info_ptr = png_create_info_struct(*png_ptr); + if (!*info_ptr) { result = -5; goto exit; } - if (setjmp(png_jmpbuf(png_ptr))) { + if (setjmp(png_jmpbuf(*png_ptr))) { result = -6; goto exit; } - png_init_io(png_ptr, fp); - png_set_sig_bytes(png_ptr, sizeof(header)); - png_read_info(png_ptr, info_ptr); + png_init_io(*png_ptr, fp); + png_set_sig_bytes(*png_ptr, sizeof(header)); + png_read_info(*png_ptr, *info_ptr); int color_type, bit_depth; - png_uint_32 width, height; - png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth, + png_get_IHDR(*png_ptr, *info_ptr, width, height, &bit_depth, &color_type, NULL, NULL, NULL); - int channels = png_get_channels(png_ptr, info_ptr); - - if (!(bit_depth <= 8 && - ((channels == 3 && color_type == PNG_COLOR_TYPE_RGB) || - (channels == 1 && (color_type == PNG_COLOR_TYPE_PALETTE || - color_type == PNG_COLOR_TYPE_GRAY))))) { - return -7; + *channels = png_get_channels(*png_ptr, *info_ptr); + + if (bit_depth == 8 && *channels == 3 && color_type == PNG_COLOR_TYPE_RGB) { + // 8-bit RGB images: great, nothing to do. + } else if (bit_depth <= 8 && *channels == 1 && color_type == PNG_COLOR_TYPE_GRAY) { + // 1-, 2-, 4-, or 8-bit gray images: expand to 8-bit gray. + png_set_expand_gray_1_2_4_to_8(*png_ptr); + } else if (bit_depth == 8 && *channels == 1 && color_type == PNG_COLOR_TYPE_PALETTE) { + // paletted images: expand to 8-bit RGB. Note that we DON'T + // currently expand the tRNS chunk (if any) to an alpha + // channel, because minui doesn't support alpha channels in + // general. + png_set_palette_to_rgb(*png_ptr); + *channels = 3; + } else { + fprintf(stderr, "minui doesn't support PNG depth %d channels %d color_type %d\n", + bit_depth, (int) channels, color_type); + result = -7; goto exit; } - size_t stride = (color_type == PNG_COLOR_TYPE_GRAY ? 1 : 4) * width; + return result; - surface = malloc_surface(stride * height); - if (surface == NULL) { - result = -8; - goto exit; + exit: + if (result < 0) { + png_destroy_read_struct(png_ptr, info_ptr, NULL); + } + if (fp != NULL) { + fclose(fp); } - unsigned char* pData = surface->data; + + return result; +} + +// "display" surfaces are transformed into the framebuffer's required +// pixel format (currently only RGBX is supported) at load time, so +// gr_blit() can be nothing more than a memcpy() for each row. The +// next two functions are the only ones that know anything about the +// framebuffer pixel format; they need to be modified if the +// framebuffer format changes (but nothing else should). + +// Allocate and return a gr_surface sufficient for storing an image of +// the indicated size in the framebuffer pixel format. +static gr_surface init_display_surface(png_uint_32 width, png_uint_32 height) { + gr_surface surface; + + surface = malloc_surface(width * height * 4); + if (surface == NULL) return NULL; + surface->width = width; surface->height = height; - surface->row_bytes = stride; - surface->pixel_bytes = (color_type == PNG_COLOR_TYPE_GRAY ? 1 : 4); + surface->row_bytes = width * 4; + surface->pixel_bytes = 4; - int alpha = (channels == 4); - png_set_expand(png_ptr); - if (color_type == PNG_COLOR_TYPE_GRAY) { - alpha = 1; - } + return surface; +} - unsigned int y; - if (channels == 3 || (channels == 1 && !alpha)) { - for (y = 0; y < height; ++y) { - unsigned char* pRow = pData + y * stride; - png_read_row(png_ptr, pRow, NULL); - - int x; - for(x = width - 1; x >= 0; x--) { - int sx = x * 3; - int dx = x * 4; - unsigned char r = pRow[sx]; - unsigned char g = pRow[sx + 1]; - unsigned char b = pRow[sx + 2]; - unsigned char a = 0xff; - pRow[dx ] = r; // r - pRow[dx + 1] = g; // g - pRow[dx + 2] = b; // b - pRow[dx + 3] = a; +// Copy 'input_row' to 'output_row', transforming it to the +// framebuffer pixel format. The input format depends on the value of +// 'channels': +// +// 1 - input is 8-bit grayscale +// 3 - input is 24-bit RGB +// 4 - input is 32-bit RGBA/RGBX +// +// 'width' is the number of pixels in the row. +static void transform_rgb_to_draw(unsigned char* input_row, + unsigned char* output_row, + int channels, int width) { + int x; + unsigned char* ip = input_row; + unsigned char* op = output_row; + + switch (channels) { + case 1: + // expand gray level to RGBX + for (x = 0; x < width; ++x) { + *op++ = *ip; + *op++ = *ip; + *op++ = *ip; + *op++ = 0xff; + ip++; } - } - } else { - for (y = 0; y < height; ++y) { - unsigned char* pRow = pData + y * stride; - png_read_row(png_ptr, pRow, NULL); - } - } - - *pSurface = (gr_surface) surface; + break; -exit: - png_destroy_read_struct(&png_ptr, &info_ptr, NULL); + case 3: + // expand RGBA to RGBX + for (x = 0; x < width; ++x) { + *op++ = *ip++; + *op++ = *ip++; + *op++ = *ip++; + *op++ = 0xff; + } + break; - if (fp != NULL) { - fclose(fp); - } - if (result < 0) { - if (surface) { - free(surface); - } + case 4: + // copy RGBA to RGBX + memcpy(output_row, input_row, width*4); + break; } - return result; } -int res_create_multi_surface(const char* name, int* frames, gr_surface** pSurface) { - char resPath[256]; +int res_create_display_surface(const char* name, gr_surface* pSurface) { + gr_surface surface = NULL; int result = 0; - unsigned char header[8]; png_structp png_ptr = NULL; png_infop info_ptr = NULL; - int i; - gr_surface* surface = NULL; + png_uint_32 width, height; + png_byte channels; *pSurface = NULL; - *frames = -1; - snprintf(resPath, sizeof(resPath)-1, "/res/images/%s.png", name); - resPath[sizeof(resPath)-1] = '\0'; - FILE* fp = fopen(resPath, "rb"); - if (fp == NULL) { - result = -1; - goto exit; - } - - size_t bytesRead = fread(header, 1, sizeof(header), fp); - if (bytesRead != sizeof(header)) { - result = -2; - goto exit; - } - - if (png_sig_cmp(header, 0, sizeof(header))) { - result = -3; - goto exit; - } + result = open_png(name, &png_ptr, &info_ptr, &width, &height, &channels); + if (result < 0) return result; - png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL); - if (!png_ptr) { - result = -4; + surface = init_display_surface(width, height); + if (surface == NULL) { + result = -8; goto exit; } - info_ptr = png_create_info_struct(png_ptr); - if (!info_ptr) { - result = -5; - goto exit; + unsigned char* p_row = malloc(width * 4); + unsigned int y; + for (y = 0; y < height; ++y) { + png_read_row(png_ptr, p_row, NULL); + transform_rgb_to_draw(p_row, surface->data + y * surface->row_bytes, channels, width); } + free(p_row); - if (setjmp(png_jmpbuf(png_ptr))) { - result = -6; - goto exit; - } + *pSurface = surface; - png_init_io(png_ptr, fp); - png_set_sig_bytes(png_ptr, sizeof(header)); - png_read_info(png_ptr, info_ptr); + exit: + png_destroy_read_struct(&png_ptr, &info_ptr, NULL); + if (result < 0 && surface != NULL) free(surface); + return result; +} - int color_type, bit_depth; +int res_create_multi_display_surface(const char* name, int* frames, gr_surface** pSurface) { + gr_surface* surface = NULL; + int result = 0; + png_structp png_ptr = NULL; + png_infop info_ptr = NULL; png_uint_32 width, height; - png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth, - &color_type, NULL, NULL, NULL); + png_byte channels; + int i; - int channels = png_get_channels(png_ptr, info_ptr); + *pSurface = NULL; + *frames = -1; - if (!(bit_depth <= 8 && - ((channels == 3 && color_type == PNG_COLOR_TYPE_RGB) || - (channels == 1 && (color_type == PNG_COLOR_TYPE_PALETTE || - color_type == PNG_COLOR_TYPE_GRAY))))) { - return -7; - goto exit; - } + result = open_png(name, &png_ptr, &info_ptr, &width, &height, &channels); + if (result < 0) return result; *frames = 1; png_textp text; @@ -257,67 +265,35 @@ int res_create_multi_surface(const char* name, int* frames, gr_surface** pSurfac goto exit; } - size_t stride = (color_type == PNG_COLOR_TYPE_GRAY ? 1 : 4) * width; - size_t pixelSize = stride * height / *frames; - surface = malloc(*frames * sizeof(gr_surface)); if (surface == NULL) { result = -8; goto exit; } for (i = 0; i < *frames; ++i) { - surface[i] = malloc_surface(pixelSize); - surface[i]->width = width; - surface[i]->height = height / *frames; - surface[i]->row_bytes = stride; - surface[i]->pixel_bytes = (color_type == PNG_COLOR_TYPE_GRAY ? 1 : 4); - } - - int alpha = (channels == 4); - png_set_expand(png_ptr); - if (color_type == PNG_COLOR_TYPE_GRAY) { - alpha = 1; + surface[i] = init_display_surface(width, height / *frames); + if (surface[i] == NULL) { + result = -8; + goto exit; + } } - png_uint_32 y; - if (channels == 3 || (channels == 1 && !alpha)) { - for (y = 0; y < height; ++y) { - int fy = y / *frames; - int fr = y % *frames; - unsigned char* pRow = surface[fr]->data + fy * stride; - png_read_row(png_ptr, pRow, NULL); - - int x; - for(x = width - 1; x >= 0; x--) { - int sx = x * 3; - int dx = x * 4; - unsigned char r = pRow[sx]; - unsigned char g = pRow[sx + 1]; - unsigned char b = pRow[sx + 2]; - unsigned char a = 0xff; - pRow[dx ] = r; // r - pRow[dx + 1] = g; // g - pRow[dx + 2] = b; // b - pRow[dx + 3] = a; - } - } - } else { - for (y = 0; y < height; ++y) { - int fy = y / *frames; - int fr = y % *frames; - unsigned char* pRow = surface[fr]->data + fy * stride; - png_read_row(png_ptr, pRow, NULL); - } + unsigned char* p_row = malloc(width * 4); + unsigned int y; + for (y = 0; y < height; ++y) { + png_read_row(png_ptr, p_row, NULL); + int frame = y % *frames; + unsigned char* out_row = surface[frame]->data + + (y / *frames) * surface[frame]->row_bytes; + transform_rgb_to_draw(p_row, out_row, channels, width); } + free(p_row); *pSurface = (gr_surface*) surface; exit: png_destroy_read_struct(&png_ptr, &info_ptr, NULL); - if (fp != NULL) { - fclose(fp); - } if (result < 0) { if (surface) { for (i = 0; i < *frames; ++i) { @@ -329,7 +305,50 @@ exit: return result; } -static int matches_locale(const char* loc) { +int res_create_alpha_surface(const char* name, gr_surface* pSurface) { + gr_surface surface = NULL; + int result = 0; + png_structp png_ptr = NULL; + png_infop info_ptr = NULL; + png_uint_32 width, height; + png_byte channels; + + *pSurface = NULL; + + result = open_png(name, &png_ptr, &info_ptr, &width, &height, &channels); + if (result < 0) return result; + + if (channels != 1) { + result = -7; + goto exit; + } + + surface = malloc_surface(width * height); + if (surface == NULL) { + result = -8; + goto exit; + } + surface->width = width; + surface->height = height; + surface->row_bytes = width; + surface->pixel_bytes = 1; + + unsigned char* p_row; + unsigned int y; + for (y = 0; y < height; ++y) { + p_row = surface->data + y * surface->row_bytes; + png_read_row(png_ptr, p_row, NULL); + } + + *pSurface = surface; + + exit: + png_destroy_read_struct(&png_ptr, &info_ptr, NULL); + if (result < 0 && surface != NULL) free(surface); + return result; +} + +static int matches_locale(const char* loc, const char* locale) { if (locale == NULL) return 0; if (strcmp(loc, locale) == 0) return 1; @@ -346,70 +365,35 @@ static int matches_locale(const char* loc) { return (strncmp(locale, loc, i) == 0 && locale[i] == '_'); } -int res_create_localized_surface(const char* name, gr_surface* pSurface) { - char resPath[256]; +int res_create_localized_alpha_surface(const char* name, + const char* locale, + gr_surface* pSurface) { gr_surface surface = NULL; int result = 0; - unsigned char header[8]; png_structp png_ptr = NULL; png_infop info_ptr = NULL; + png_uint_32 width, height; + png_byte channels; *pSurface = NULL; - snprintf(resPath, sizeof(resPath)-1, "/res/images/%s.png", name); - resPath[sizeof(resPath)-1] = '\0'; - FILE* fp = fopen(resPath, "rb"); - if (fp == NULL) { - result = -1; - goto exit; - } - - size_t bytesRead = fread(header, 1, sizeof(header), fp); - if (bytesRead != sizeof(header)) { - result = -2; - goto exit; - } - - if (png_sig_cmp(header, 0, sizeof(header))) { - result = -3; - goto exit; - } - - png_ptr = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL); - if (!png_ptr) { - result = -4; - goto exit; - } - - info_ptr = png_create_info_struct(png_ptr); - if (!info_ptr) { - result = -5; - goto exit; - } - - if (setjmp(png_jmpbuf(png_ptr))) { - result = -6; + if (locale == NULL) { + surface = malloc_surface(0); + surface->width = 0; + surface->height = 0; + surface->row_bytes = 0; + surface->pixel_bytes = 1; goto exit; } - png_init_io(png_ptr, fp); - png_set_sig_bytes(png_ptr, sizeof(header)); - png_read_info(png_ptr, info_ptr); - - int color_type, bit_depth; - png_uint_32 width, height; - png_get_IHDR(png_ptr, info_ptr, &width, &height, &bit_depth, - &color_type, NULL, NULL, NULL); - int channels = png_get_channels(png_ptr, info_ptr); + result = open_png(name, &png_ptr, &info_ptr, &width, &height, &channels); + if (result < 0) return result; - if (!(bit_depth <= 8 && - (channels == 1 && color_type == PNG_COLOR_TYPE_GRAY))) { - return -7; + if (channels != 1) { + result = -7; goto exit; } - png_set_expand(png_ptr); - unsigned char* row = malloc(width); png_uint_32 y; for (y = 0; y < height; ++y) { @@ -419,7 +403,7 @@ int res_create_localized_surface(const char* name, gr_surface* pSurface) { int len = row[4]; char* loc = (char*)row+5; - if (y+1+h >= height || matches_locale(loc)) { + if (y+1+h >= height || matches_locale(loc, locale)) { printf(" %20s: %s (%d x %d @ %d)\n", name, loc, w, h, y); surface = malloc_surface(w*h); @@ -427,8 +411,6 @@ int res_create_localized_surface(const char* name, gr_surface* pSurface) { result = -8; goto exit; } - unsigned char* pData = surface->data; - surface->width = w; surface->height = h; surface->row_bytes = w; @@ -437,7 +419,7 @@ int res_create_localized_surface(const char* name, gr_surface* pSurface) { int i; for (i = 0; i < h; ++i, ++y) { png_read_row(png_ptr, row, NULL); - memcpy(pData + i*w, row, w); + memcpy(surface->data + i*w, row, w); } *pSurface = (gr_surface) surface; @@ -452,15 +434,7 @@ int res_create_localized_surface(const char* name, gr_surface* pSurface) { exit: png_destroy_read_struct(&png_ptr, &info_ptr, NULL); - - if (fp != NULL) { - fclose(fp); - } - if (result < 0) { - if (surface) { - free(surface); - } - } + if (result < 0 && surface != NULL) free(surface); return result; } -- cgit v1.1