Fix png graphics load / display on AArch64
This is mostly kang from AOSP resources.c for loading png files
into RAM, but for ease of compatibility we retained the older
gr_surface data types throughout and ensured that we retain
support for alpha blended png files.
Change-Id: Ieea552173d3bfe885460407be73088bbad75663f
diff --git a/minuitwrp/resources.c b/minuitwrp/resources.c
index 4dd10a9..6f6d13b 100644
--- a/minuitwrp/resources.c
+++ b/minuitwrp/resources.c
@@ -42,25 +42,29 @@
return x;
}
-int res_create_surface_png(const char* name, gr_surface* pSurface) {
- GGLSurface* surface = NULL;
- int result = 0;
+#define SURFACE_DATA_ALIGNMENT 8
+
+static GGLSurface* malloc_surface(size_t data_size) {
+ unsigned char* temp = malloc(sizeof(GGLSurface) + data_size + SURFACE_DATA_ALIGNMENT);
+ if (temp == NULL) return NULL;
+ GGLSurface* surface = (GGLSurface*) temp;
+ surface->data = temp + sizeof(GGLSurface) +
+ (SURFACE_DATA_ALIGNMENT - (sizeof(GGLSurface) % SURFACE_DATA_ALIGNMENT));
+ return surface;
+}
+
+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];
unsigned char header[8];
- png_structp png_ptr = NULL;
- png_infop info_ptr = NULL;
+ int result = 0;
- FILE* fp = fopen(name, "rb");
+ snprintf(resPath, sizeof(resPath)-1, "/res/images/%s.png", name);
+ resPath[sizeof(resPath)-1] = '\0';
+ FILE* fp = fopen(resPath, "rb");
if (fp == NULL) {
- char resPath[256];
-
- snprintf(resPath, sizeof(resPath)-1, "/res/images/%s.png", name);
- resPath[sizeof(resPath)-1] = '\0';
- fp = fopen(resPath, "rb");
- if (fp == NULL)
- {
- result = -1;
- goto exit;
- }
+ result = -1;
+ goto exit;
}
size_t bytesRead = fread(header, 1, sizeof(header), fp);
@@ -74,105 +78,173 @@
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_set_packing(png_ptr);
-
- 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;
- size_t 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);
- png_byte channels = png_get_channels(png_ptr, info_ptr);
- size_t stride = 4 * width;
- size_t pixelSize = stride * height;
+ *channels = png_get_channels(*png_ptr, *info_ptr);
- if (!(bit_depth == 8 &&
- ((channels == 3 && color_type == PNG_COLOR_TYPE_RGB) ||
- (channels == 4 && color_type == PNG_COLOR_TYPE_RGBA) ||
- (channels == 1 && color_type == PNG_COLOR_TYPE_PALETTE)))) {
- return -7;
+ /*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, *channels, color_type);
+ result = -7;
goto exit;
- }
-
- surface = malloc(sizeof(GGLSurface) + pixelSize);
- if (surface == NULL) {
- result = -8;
- goto exit;
- }
- unsigned char* pData = (unsigned char*) (surface + 1);
- surface->version = sizeof(GGLSurface);
- surface->width = width;
- surface->height = height;
- surface->stride = width; /* Yes, pixels, not bytes */
- surface->data = pData;
- surface->format = (channels == 3) ?
- GGL_PIXEL_FORMAT_RGBX_8888 : GGL_PIXEL_FORMAT_RGBA_8888;
-
+ }*/
if (color_type == PNG_COLOR_TYPE_PALETTE) {
png_set_palette_to_rgb(png_ptr);
}
- int y;
- if (channels < 4) {
- for (y = 0; y < (int) height; ++y) {
- unsigned char* pRow = pData + y * stride;
- png_read_row(png_ptr, pRow, NULL);
+ return result;
- 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 < (int) height; ++y) {
- unsigned char* pRow = pData + y * stride;
- png_read_row(png_ptr, pRow, NULL);
- }
+ exit:
+ if (result < 0) {
+ png_destroy_read_struct(png_ptr, info_ptr, NULL);
}
-
- *pSurface = (gr_surface) surface;
-
-exit:
- png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
-
if (fp != NULL) {
fclose(fp);
}
- if (result < 0) {
- if (surface) {
- free(surface);
- }
+
+ 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 GGLSurface* init_display_surface(png_uint_32 width, png_uint_32 height) {
+ GGLSurface* surface;
+
+ surface = (GGLSurface*) malloc_surface(width * height * 4);
+ if (surface == NULL) return NULL;
+
+ surface->version = sizeof(GGLSurface);
+ surface->width = width;
+ surface->height = height;
+ surface->stride = width;
+
+ return surface;
+}
+
+// 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++;
+ }
+ break;
+
+ case 3:
+ // expand RGBA to RGBX
+ for (x = 0; x < width; ++x) {
+ *op++ = *ip++;
+ *op++ = *ip++;
+ *op++ = *ip++;
+ *op++ = 0xff;
+ }
+ break;
+
+ case 4:
+ // copy RGBA to RGBX
+ memcpy(output_row, input_row, width*4);
+ break;
}
+}
+
+int res_create_surface_png(const char* name, gr_surface* pSurface) {
+ GGLSurface* 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;
+
+ surface = init_display_surface(width, height);
+ if (surface == NULL) {
+ result = -8;
+ 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 * width * 4, channels, width);
+ }
+ free(p_row);
+
+ if (channels == 3)
+ surface->format = GGL_PIXEL_FORMAT_RGBX_8888;
+ else
+ surface->format = GGL_PIXEL_FORMAT_RGBA_8888;
+
+ *pSurface = (gr_surface) surface;
+
+ exit:
+ png_destroy_read_struct(&png_ptr, &info_ptr, NULL);
+ if (result < 0 && surface != NULL) free(surface);
return result;
}