assemble a splash preview if none was found (#277)

include/conversion.h

@@ -0,0 +1,9 @@
+#ifndef CONVERISON_H
+#define CONVERISON_H
+
+#include "common.h"
+
+size_t bin_to_abgr(char ** bufp, size_t size);
+size_t png_to_abgr(char ** bufp, size_t size);
+
+#endif

include/loading.h

@@ -31,6 +31,12 @@
 #include "music.h"
 #include <jansson.h>
 
+// These values assume a horizontal orientation
+#define TOP_SCREEN_WIDTH 400
+#define BOTTOM_SCREEN_WIDTH 320
+#define SCREEN_HEIGHT 240
+#define SCREEN_COLOR_DEPTH 4
+
 enum ICON_IDS_OFFSET {
     ICONS_ABOVE = 0,
     ICONS_VISIBLE,
@@ -118,7 +124,7 @@ void sort_by_filename(Entry_List_s * list);
 
 void delete_entry(Entry_s * entry, bool is_file);
 Result load_entries(const char * loading_path, Entry_List_s * list);
-bool load_preview_from_buffer(void * buf, u32 size, C2D_Image * preview_image, int * preview_offset);
+bool load_preview_from_buffer(char * row_pointers, u32 size, C2D_Image * preview_image, int * preview_offset);
 bool load_preview(Entry_List_s list, C2D_Image * preview_image, int * preview_offset);
 void free_preview(C2D_Image preview_image);
 Result load_audio(Entry_s, audio_s *);

source/conversion.c

@@ -0,0 +1,129 @@
+#include "conversion.h"
+#include "draw.h"
+
+#include <png.h>
+
+static void rotate_agbr_counterclockwise(char ** bufp, size_t size, size_t width)
+{
+    uint32_t * buf = (uint32_t*)*bufp;
+    uint32_t * out = malloc(size);
+
+    size_t pixel_count = (size/4);
+    size_t height = pixel_count/width;
+
+    for (uint32_t h = 0; h < height; ++h)
+    {
+        for (uint32_t w = 0; w < width; ++w)
+        {
+            size_t buf_index = (w + (h * width));
+            size_t out_index = (height * (width-1)) - (height * w) + h;
+
+            out[out_index] = buf[buf_index];
+        }
+    }
+
+    free(*bufp);
+    *bufp = (char*)out;
+}
+
+size_t bin_to_abgr(char ** bufp, size_t size)
+{
+    size_t out_size = (size / 3) * 4;
+    char* buf = malloc(out_size);
+
+    for (size_t i = 0, j = 0; i < size; i+=3, j+=4)
+    {
+        (buf+j)[0] = 0xFF;         // A
+        (buf+j)[1] = (*bufp+i)[0]; // B
+        (buf+j)[2] = (*bufp+i)[1]; // G
+        (buf+j)[3] = (*bufp+i)[2]; // R
+    }
+    free(*bufp);
+    *bufp = buf;
+
+    // splash screens contain the raw framebuffer to put on the screen
+    // because the screens are mounted at a 90 degree angle we also need to rotate
+    // the output
+    rotate_agbr_counterclockwise(bufp, out_size, 240);
+
+    return out_size;
+}
+
+size_t png_to_abgr(char ** bufp, size_t size)
+{
+    size_t out_size = 0;
+    if(size < 8 || png_sig_cmp((png_bytep)*bufp, 0, 8))
+    {
+        throw_error("Invalid preview.png", ERROR_LEVEL_WARNING);
+        return out_size;
+    }
+
+    uint32_t * buf = (uint32_t*)*bufp;
+
+    FILE * fp = fmemopen(buf, size, "rb");;
+    png_bytep * row_pointers = NULL;
+
+    png_structp png = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
+    png_infop info = png_create_info_struct(png);
+
+    png_init_io(png, fp);
+    png_read_info(png, info);
+
+    u32 width = png_get_image_width(png, info);
+    u32 height = png_get_image_height(png, info);
+
+    png_byte color_type = png_get_color_type(png, info);
+    png_byte bit_depth  = png_get_bit_depth(png, info);
+
+    // Read any color_type into 8bit depth, ABGR format.
+    // See http://www.libpng.org/pub/png/libpng-manual.txt
+
+    if(bit_depth == 16)
+        png_set_strip_16(png);
+
+    if(color_type == PNG_COLOR_TYPE_PALETTE)
+        png_set_palette_to_rgb(png);
+
+    // PNG_COLOR_TYPE_GRAY_ALPHA is always 8 or 16bit depth.
+    if(color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8)
+        png_set_expand_gray_1_2_4_to_8(png);
+
+    if(png_get_valid(png, info, PNG_INFO_tRNS))
+        png_set_tRNS_to_alpha(png);
+
+    // These color_type don't have an alpha channel then fill it with 0xff.
+    if(color_type == PNG_COLOR_TYPE_RGB ||
+       color_type == PNG_COLOR_TYPE_GRAY ||
+       color_type == PNG_COLOR_TYPE_PALETTE)
+        png_set_add_alpha(png, 0xFF, PNG_FILLER_BEFORE);
+
+    if(color_type == PNG_COLOR_TYPE_GRAY ||
+       color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
+        png_set_gray_to_rgb(png);
+
+    //output ABGR
+    png_set_bgr(png);
+    png_set_swap_alpha(png);
+
+    png_read_update_info(png, info);
+
+    row_pointers = malloc(sizeof(png_bytep) * height);
+    out_size = sizeof(u32) * (width * height);
+    u32 * out = malloc(out_size);
+    for(u32 y = 0; y < height; y++)
+    {
+        row_pointers[y] = (png_bytep)(out + (width * y));
+    }
+
+    png_read_image(png, row_pointers);
+
+    png_destroy_read_struct(&png, &info, NULL);
+
+    if (fp) fclose(fp);
+    if (row_pointers) free(row_pointers);
+
+    free(*bufp);
+    *bufp = (char*)out;
+
+    return out_size;
+}

source/loading.c

@@ -29,6 +29,7 @@
 #include "unicode.h"
 #include "music.h"
 #include "draw.h"
+#include "conversion.h"
 
 #include <png.h>
 
@@ -449,77 +450,10 @@ void load_icons_thread(void * void_arg)
     while(arg->run_thread);
 }
 
-bool load_preview_from_buffer(void * buf, u32 size, C2D_Image * preview_image, int * preview_offset)
+bool load_preview_from_buffer(char * row_pointers, u32 size, C2D_Image * preview_image, int * preview_offset)
 {
-    if(size < 8 || png_sig_cmp(buf, 0, 8))
+    int height = SCREEN_HEIGHT * 2;
-    {
+    int width = (uint32_t)((size / 4) / height);
-        throw_error("Invalid preview.png", ERROR_LEVEL_WARNING);
-        return false;
-    }
-
-    png_structp png = png_create_read_struct(PNG_LIBPNG_VER_STRING, NULL, NULL, NULL);
-
-    png_infop info = png_create_info_struct(png);
-
-    if(setjmp(png_jmpbuf(png)))
-    {
-        png_destroy_read_struct(&png, &info, NULL);
-        return false;
-    }
-
-    FILE * fp = fmemopen(buf, size, "rb");
-
-    png_init_io(png, fp);
-    png_read_info(png, info);
-
-    int width = png_get_image_width(png, info);
-    int height = png_get_image_height(png, info);
-
-    png_byte color_type = png_get_color_type(png, info);
-    png_byte bit_depth  = png_get_bit_depth(png, info);
-
-    // Read any color_type into 8bit depth, ABGR format.
-    // See http://www.libpng.org/pub/png/libpng-manual.txt
-
-    if(bit_depth == 16)
-        png_set_strip_16(png);
-
-    if(color_type == PNG_COLOR_TYPE_PALETTE)
-        png_set_palette_to_rgb(png);
-
-    // PNG_COLOR_TYPE_GRAY_ALPHA is always 8 or 16bit depth.
-    if(color_type == PNG_COLOR_TYPE_GRAY && bit_depth < 8)
-        png_set_expand_gray_1_2_4_to_8(png);
-
-    if(png_get_valid(png, info, PNG_INFO_tRNS))
-        png_set_tRNS_to_alpha(png);
-
-    // These color_type don't have an alpha channel then fill it with 0xff.
-    if(color_type == PNG_COLOR_TYPE_RGB ||
-       color_type == PNG_COLOR_TYPE_GRAY ||
-       color_type == PNG_COLOR_TYPE_PALETTE)
-        png_set_add_alpha(png, 0xFF, PNG_FILLER_BEFORE);
-
-    if(color_type == PNG_COLOR_TYPE_GRAY ||
-       color_type == PNG_COLOR_TYPE_GRAY_ALPHA)
-        png_set_gray_to_rgb(png);
-
-    //output ABGR
-    png_set_bgr(png);
-    png_set_swap_alpha(png);
-
-    png_read_update_info(png, info);
-
-    png_bytep * row_pointers = malloc(sizeof(png_bytep) * height);
-    for(int y = 0; y < height; y++) {
-        row_pointers[y] = (png_byte*)malloc(png_get_rowbytes(png,info));
-    }
-
-    png_read_image(png, row_pointers);
-
-    fclose(fp);
-    png_destroy_read_struct(&png, &info, NULL);
-
 
     free_preview(*preview_image);
 
@@ -540,20 +474,16 @@ bool load_preview_from_buffer(void * buf, u32 size, C2D_Image * preview_image, i
     memset(preview_image->tex->data, 0, preview_image->tex->size);
 
     for(int j = 0; j < height; j++) {
-        png_bytep row = row_pointers[j];
+        png_bytep row = (png_bytep)(row_pointers + (width * 4 * j));
         for(int i = 0; i < width; i++) {
             png_bytep px = &(row[i * 4]);
             u32 dst = ((((j >> 3) * (512 >> 3) + (i >> 3)) << 6) + ((i & 1) | ((j & 1) << 1) | ((i & 2) << 1) | ((j & 2) << 2) | ((i & 4) << 2) | ((j & 4) << 3))) * 4;
 
             memcpy(preview_image->tex->data + dst, px, sizeof(u32));
         }
-
-        free(row_pointers[j]);
     }
 
-    free(row_pointers);
+    *preview_offset = (width - TOP_SCREEN_WIDTH) / 2;
-
-    *preview_offset = (width-400)/2;
 
     return true;
 }
@@ -570,11 +500,65 @@ bool load_preview(Entry_List_s list, C2D_Image * preview_image, int * preview_of
     char *preview_buffer = NULL;
     u64 size = load_data("/preview.png", entry, &preview_buffer);
 
-    if(!size)
+    if(size)
+    {
+        if (!(size = png_to_abgr(&preview_buffer, size)))
+        {
+            return false;
+        }
+    }
+    else
     {
         free(preview_buffer);
-        throw_error("No preview found.", ERROR_LEVEL_WARNING);
+
-        return false;
+        const int top_size =  TOP_SCREEN_WIDTH * SCREEN_HEIGHT * SCREEN_COLOR_DEPTH;
+        const int out_size = top_size * 2;
+
+        char * rgba_buffer = malloc(out_size);
+        memset(rgba_buffer, 0, out_size);
+        bool found_splash = false;
+
+        // try to assembly a preview from the splash screens
+        size = load_data("/splash.bin", entry, &preview_buffer);
+        if (size)
+        {
+            found_splash = true;
+            bin_to_abgr(&preview_buffer, size);
+
+            memcpy(rgba_buffer, preview_buffer, top_size);
+            free(preview_buffer);
+        }
+
+        size = load_data("/splashbottom.bin", entry, &preview_buffer);
+        if (size)
+        {
+            found_splash = true;
+            bin_to_abgr(&preview_buffer, size);
+
+            const int buffer_width = TOP_SCREEN_WIDTH * SCREEN_COLOR_DEPTH;
+            const int bottom_buffer_width = BOTTOM_SCREEN_WIDTH * SCREEN_COLOR_DEPTH;
+            const int bottom_centered_offset = (TOP_SCREEN_WIDTH - BOTTOM_SCREEN_WIDTH) / 2;
+
+            // Store the bottom splash screen under the top splash and centered
+            for (int i = 0; i < SCREEN_HEIGHT; ++i)
+                memcpy(
+                    rgba_buffer + top_size + (buffer_width * i) + (bottom_centered_offset * SCREEN_COLOR_DEPTH),
+                    preview_buffer + (bottom_buffer_width * i),
+                    bottom_buffer_width
+                );
+    
+            free(preview_buffer);
+        }
+
+        if (!found_splash)
+        {
+            free(rgba_buffer);
+            throw_error("No preview found.", ERROR_LEVEL_WARNING);
+            return false;
+        }
+
+        size = out_size;
+        preview_buffer = rgba_buffer;
     }
 
     bool ret = load_preview_from_buffer(preview_buffer, size, preview_image, preview_offset);

source/remote.c

@@ -32,6 +32,7 @@
 #include "unicode.h"
 #include "music.h"
 #include "urls.h"
+#include "conversion.h"
 
 // forward declaration of special case used only here
 // TODO: replace this travesty with a proper handler
@@ -296,7 +297,18 @@ static bool load_remote_preview(Entry_s * entry, C2D_Image * preview_image, int
         return false;
     }
 
-    bool ret = load_preview_from_buffer(preview_png, preview_size, preview_image, preview_offset);
+    char * preview_buf = malloc(preview_size);
+    u32 preview_buf_size = preview_size;
+    memcpy(preview_buf, preview_png, preview_size);
+
+    if (!(preview_buf_size = png_to_abgr(&preview_buf, preview_buf_size)))
+    {
+        free(preview_buf);
+        return false;
+    }
+
+    bool ret = load_preview_from_buffer(preview_buf, preview_buf_size, preview_image, preview_offset);
+    free(preview_buf);
 
     if (ret && not_cached) // only save the preview if it loaded correctly - isn't corrupted
     {