Improved loading game frames

CMakeLists.txt

@@ -164,7 +164,6 @@ else()
 
   if (NINTENDO_3DS)
     set(ROMFS_DIR "${CMAKE_CURRENT_BINARY_DIR}/romfs")
-    file(COPY ${CMAKE_CURRENT_SOURCE_DIR}/export/data DESTINATION ${ROMFS_DIR})
     file(COPY ${CMAKE_CURRENT_SOURCE_DIR}/export/carts DESTINATION ${ROMFS_DIR})
     set(SMDH_FILE "${CMAKE_CURRENT_BINARY_DIR}/${APP_NAME}.smdh")
     ctr_generate_smdh("${SMDH_FILE}"

cmake/project_config.cmake

@@ -6,7 +6,6 @@ set(project_sources
   ${CMAKE_CURRENT_SOURCE_DIR}/src/app.c
   ${CMAKE_CURRENT_SOURCE_DIR}/src/auxiliary.c
   ${CMAKE_CURRENT_SOURCE_DIR}/src/core.c
-  ${CMAKE_CURRENT_SOURCE_DIR}/src/image_loader.c
   ${CMAKE_CURRENT_SOURCE_DIR}/src/memory.c
   ${CMAKE_CURRENT_SOURCE_DIR}/src/p8scii.c
   ${CMAKE_CURRENT_SOURCE_DIR}/src/lexaloffle/p8_compress.c

res/open8.pkg

@@ -14,7 +14,6 @@
 "..\out\build\N-Gage\open8.app"-"E:\System\Apps\open8\open8.app"
 "..\out\build\N-Gage\open8.rsc"-"E:\System\Apps\open8\open8.rsc"
 "..\out\build\N-Gage\open8.aif"-"E:\System\Apps\open8\open8.aif"
-"..\export\data\frame.png"-"E:\System\Apps\open8\data\frame.png"
 "..\export\carts\automata.p8.png"-"E:\System\Apps\open8\carts\automata.p8.png"
 "..\export\carts\api.p8.png"-"E:\System\Apps\open8\carts\api.p8.png"
 "..\export\carts\demo.p8.png"-"E:\System\Apps\open8\carts\demo.p8.png"

src/config.h

@@ -12,35 +12,35 @@
 
 #include "SDL3/SDL.h"
 
-#define SCREEN_SIZE 128
 
 #ifdef __SYMBIAN32__
 #define SCALE 1
 #define WINDOW_W 176
 #define WINDOW_H 208
 #define WINDOW_FLAGS 0
-#define FRAME_OFFSET_X 0
-#define FRAME_OFFSET_Y 0
-#define SCREEN_OFFSET_X 24
-#define SCREEN_OFFSET_Y 25
+#define FRAME_OFFSET_X 8
+#define FRAME_OFFSET_Y 1
 #elif defined __3DS__
 #define SCALE 1
 #define WINDOW_W 400
 #define WINDOW_H 240
 #define WINDOW_FLAGS 0
-#define FRAME_OFFSET_X 112
-#define FRAME_OFFSET_Y 16
-#define SCREEN_OFFSET_X FRAME_OFFSET_X + 24
-#define SCREEN_OFFSET_Y FRAME_OFFSET_Y + 25
+#define FRAME_OFFSET_X 120
+#define FRAME_OFFSET_Y 17
 #else
 #define SCALE 3
 #define WINDOW_W 176
 #define WINDOW_H 208
 #define WINDOW_FLAGS (SDL_WINDOW_UTILITY)
-#define FRAME_OFFSET_X 0
-#define FRAME_OFFSET_Y 0
-#define SCREEN_OFFSET_X 24
-#define SCREEN_OFFSET_Y 25
+#define FRAME_OFFSET_X 8
+#define FRAME_OFFSET_Y 1
 #endif
 
+#define FRAME_W 160
+#define FRAME_H 205
+
+#define SCREEN_OFFSET_X FRAME_OFFSET_X + 16
+#define SCREEN_OFFSET_Y FRAME_OFFSET_Y + 24
+#define SCREEN_SIZE 128
+
 #endif // CONFIG_H

src/core.c

@@ -16,8 +16,11 @@
 #include "api.h"
 #include "config.h"
 #include "core.h"
-#include "image_loader.h"
 #include "memory.h"
+
+#define STBI_ONLY_PNG
+#define STBI_NO_THREAD_LOCALS
+#define STB_IMAGE_IMPLEMENTATION
 #include "misc/stb_image.h"
 
 #ifdef _WIN32
@@ -27,8 +30,6 @@
 #endif
 #include <string.h>
 
-static SDL_Texture* frame;
-
 static char** available_carts;
 static int num_carts;
 
@@ -83,13 +84,13 @@ static void destroy_vm(void)
     lua_close(vm);
 }
 
-static void extract_pico8_data(const uint8_t* image_data, uint8_t* cart_data)
+static void extract_pico8_data(uint8_t* image_data, uint8_t* cart_data)
 {
     size_t data_index = 0;
     size_t pixel_count = CART_WIDTH * CART_HEIGHT;
 
     // Each Pico-8 byte is stored as the two least significant bits of each of the four
-    // channels, ordered ABGR (E.g: the A channel stores the 2 most significant bits in
+    // channels, ordered ARGB (E.g: the A channel stores the 2 most significant bits in
     // the bytes).  The image is 160 pixels wide and 205 pixels high, for a possible
     // storage of 32,800 (0x8020) bytes.
 
@@ -100,17 +101,20 @@ static void extract_pico8_data(const uint8_t* image_data, uint8_t* cart_data)
             break;
         }
 
-        // ABGR8888
-        uint8_t A = image_data[i * 4];     // A channel
-        uint8_t B = image_data[i * 4 + 1]; // B channel
-        uint8_t G = image_data[i * 4 + 2]; // G channel
-        uint8_t R = image_data[i * 4 + 3]; // R channel
+        // stb_image stores components in RGBA32 order
+        uint8_t R = image_data[i * 4];     // R channel
+        uint8_t G = image_data[i * 4 + 1]; // G channel
+        uint8_t B = image_data[i * 4 + 2]; // B channel
+        uint8_t A = image_data[i * 4 + 3]; // A channel
 
         // Extract the 2 least significant bits from each channel.
-        uint8_t byte = ((B & 0x03) << 6) | ((G & 0x03) << 4) | ((R & 0x03) << 2) | (A & 0x03);
+        uint8_t byte = ((A & 0x03) << 6) | ((R & 0x03) << 4) | ((G & 0x03) << 2) | ((B & 0x03) << 0);
 
-        // Swap nibbles.
-        byte = (byte >> 4) | (byte << 4);
+        // Clean up graphical artifacts visible on 32bpp displays
+        image_data[i * 4]     = (R & 0xFC) | (R >> 6);
+        image_data[i * 4 + 1] = (G & 0xFC) | (G >> 6);
+        image_data[i * 4 + 2] = (B & 0xFC) | (B >> 6);
+        image_data[i * 4 + 3] = (A & 0xFC) | (A >> 6);
 
         cart_data[data_index] = byte;
         data_index++;
@@ -189,39 +193,58 @@ static int load_cart(SDL_Renderer* renderer, const char* file_name, cart_t* cart
     long file_size = ftell(file);
     fseek(file, 0, SEEK_SET);
 
-    cart->data = (uint8_t*)SDL_calloc(file_size, sizeof(uint8_t));
-    if (!cart->data)
+    uint8_t* data = (uint8_t*)SDL_calloc(file_size, sizeof(uint8_t));
+    if (!data)
     {
         SDL_Log("Couldn't allocate memory for cart data");
         fclose(file);
         return 0;
     }
-    fread(cart->data, 1, file_size, file);
-    cart->size = file_size;
+    fread(data, 1, file_size, file);
     fclose(file);
 
-    uint32_t* image_data = (uint32_t*)stbi_load_from_memory(cart->data, cart->size, &width, &height, &bpp, 4);
+    uint8_t* image_data = stbi_load_from_memory(data, file_size, &width, &height, &bpp, 4);
     if (!image_data)
     {
         SDL_Log("Couldn't load image data: %s", stbi_failure_reason());
+        SDL_free(data);
         return 0;
     }
+    SDL_free(data);
 
     if (width != CART_WIDTH || height != CART_HEIGHT)
     {
         SDL_Log("Invalid image size: %dx%d", width, height);
+        stbi_image_free(image_data);
         return 0;
     }
 
-    SDL_Surface* surface = SDL_CreateSurfaceFrom(width, height, SDL_PIXELFORMAT_ABGR8888, image_data, width * 4);
+    extract_pico8_data(image_data, cart->cart_data);
+
+    SDL_Surface* surface = SDL_CreateSurfaceFrom(width, height, SDL_PIXELFORMAT_RGBA32, image_data, width * 4);
     if (!surface)
     {
         SDL_Log("Couldn't create surface: %s", SDL_GetError());
         stbi_image_free(image_data);
         return 0;
     }
 
-    extract_pico8_data((const uint8_t*)image_data, cart->cart_data);
+    cart->image = SDL_CreateTextureFromSurface(renderer, surface);
+    if (!cart->image)
+    {
+        SDL_Log("Couldn't create texture: %s", SDL_GetError());
+        SDL_DestroySurface(surface);
+        stbi_image_free(image_data);
+        return 0;
+    }
+
+    SDL_DestroySurface(surface);
+    stbi_image_free(image_data);
+
+    if (!SDL_SetTextureScaleMode(cart->image, SDL_SCALEMODE_NEAREST))
+    {
+        SDL_Log("Couldn't set texture scale mode: %s", SDL_GetError());
+    }
 
     uint32_t header = *(uint32_t*)&cart->cart_data[0x4300];
     int status = 0;
@@ -230,7 +253,7 @@ static int load_cart(SDL_Renderer* renderer, const char* file_name, cart_t* cart
     if (!cart->code)
     {
         SDL_Log("Could not allocate code memory: %s", SDL_GetError());
-        stbi_image_free(image_data);
+        SDL_DestroyTexture(cart->image);
         return 0;
     }
 
@@ -266,7 +289,7 @@ static int load_cart(SDL_Renderer* renderer, const char* file_name, cart_t* cart
     if (!cart->code)
     {
         SDL_Log("Could not re-allocate code memory: %s", SDL_GetError());
-        stbi_image_free(image_data);
+        SDL_DestroyTexture(cart->image);
         return 0;
     }
 
@@ -280,20 +303,6 @@ static int load_cart(SDL_Renderer* renderer, const char* file_name, cart_t* cart
         patch_cart_code(cart);
     }
 
-    cart->image = SDL_CreateTextureFromSurface(renderer, surface);
-    if (!cart->image)
-    {
-        SDL_Log("Couldn't create texture: %s", SDL_GetError());
-        return 0;
-    }
-    SDL_DestroySurface(surface);
-    stbi_image_free(image_data);
-
-    if (!SDL_SetTextureScaleMode(cart->image, SDL_SCALEMODE_NEAREST))
-    {
-        SDL_Log("Couldn't set texture scale mode: %s", SDL_GetError());
-    }
-
     return 1;
 }
 
@@ -314,12 +323,6 @@ static void destroy_cart(cart_t* cart)
         SDL_free(cart->code);
     }
     cart->code = NULL;
-
-    if (cart->data)
-    {
-        SDL_free(cart->data);
-    }
-    cart->data = NULL;
 }
 
 static bool is_function_present(lua_State* L, const char* func_name)
@@ -432,29 +435,16 @@ static void render_cartridge(SDL_Renderer* renderer)
 {
     SDL_SetRenderTarget(renderer, NULL);
 
-    SDL_FRect source;
     SDL_FRect dest;
-    SDL_FRect frame_dest;
-
-    source.x = 16.f;
-    source.y = 24.f;
-    source.w = SCREEN_SIZE;
-    source.h = SCREEN_SIZE;
-
-    dest.x = SCREEN_OFFSET_X;
-    dest.y = SCREEN_OFFSET_Y;
-    dest.w = SCREEN_SIZE;
-    dest.h = SCREEN_SIZE;
 
-    frame_dest.x = FRAME_OFFSET_X;
-    frame_dest.y = FRAME_OFFSET_Y;
-    frame_dest.w = 176.f;
-    frame_dest.h = 208.f;
+    dest.x = FRAME_OFFSET_X;
+    dest.y = FRAME_OFFSET_Y;
+    dest.w = FRAME_W;
+    dest.h = FRAME_H;
 
     SDL_SetRenderDrawColor(renderer, 0x31, 0x31, 0x31, 0xff);
     SDL_RenderClear(renderer);
-    SDL_RenderTexture(renderer, frame, NULL, &frame_dest);
-    SDL_RenderTexture(renderer, cart.image, &source, &dest);
+    SDL_RenderTexture(renderer, cart.image, NULL, &dest);
 }
 
 bool init_core(SDL_Renderer* renderer)
@@ -466,13 +456,6 @@ bool init_core(SDL_Renderer* renderer)
     selection = 0;
     prev_selection = !selection;
 
-    SDL_snprintf(path, sizeof(path), "%sdata/frame.png", SDL_GetBasePath());
-    frame = load_image(renderer, path, &width, &height, &bpp);
-    if (!frame)
-    {
-        return false;
-    }
-
     SDL_snprintf(path, sizeof(path), "%scarts", SDL_GetBasePath());
 
     DIR* dir = opendir(path);
@@ -524,10 +507,6 @@ void destroy_core(void)
     {
         SDL_free(available_carts);
     }
-    if (frame)
-    {
-        SDL_DestroyTexture(frame);
-    }
 }
 
 bool handle_events(SDL_Renderer* renderer, SDL_Event* event)

src/core.h

@@ -22,8 +22,6 @@
 typedef struct cart
 {
     SDL_Texture* image;
-    uint8_t* data;
-    uint32_t size;
 
     uint8_t cart_data[0x8020];
     uint8_t* code;