Move SDL_LoadBMP call to libopenrct2ui (#5616)

src/openrct2-ui/UiContext.cpp

@@ -27,6 +27,7 @@
 #include <openrct2/core/Math.hpp>
 #include <openrct2/core/String.hpp>
 #include <openrct2/drawing/IDrawingEngine.h>
+#include <openrct2/localisation/string_ids.h>
 #include <openrct2/platform/Platform2.h>
 #include <openrct2/ui/UiContext.h>
 #include <openrct2/Version.h>
@@ -43,6 +44,7 @@ extern "C"
     #include <openrct2/input.h>
     #include <openrct2/interface/console.h>
     #include <openrct2/interface/window.h>
+    #include <openrct2/windows/error.h>
 }
 
 using namespace OpenRCT2;
@@ -574,6 +576,70 @@ public:
         return _windowManager;
     }
 
+    bool ReadBMP(void * * outPixels, uint32 * outWidth, uint32 * outHeight, const std::string &path) override
+    {
+        auto bitmap = SDL_LoadBMP(path.c_str());
+        if (bitmap != nullptr)
+        {
+            sint32 numChannels = bitmap->format->BytesPerPixel;
+            if (numChannels < 3 || bitmap->format->BitsPerPixel < 24)
+            {
+                window_error_open(STR_HEIGHT_MAP_ERROR, STR_ERROR_24_BIT_BITMAP);
+                SDL_FreeSurface(bitmap);
+                return false;
+            }
+
+            // Copy pixels over, then discard the surface
+            *outPixels = nullptr;
+            *outWidth = bitmap->w;
+            *outHeight = bitmap->h;
+            if (SDL_LockSurface(bitmap) == 0)
+            {
+                *outPixels = malloc(bitmap->w * bitmap->h * 4);
+                memset(*outPixels, 0xFF, bitmap->w * bitmap->h);
+
+                auto src = (const uint8 *)bitmap->pixels;
+                auto dst = (uint8 *)*outPixels;
+                if (numChannels == 4)
+                {
+                    for (sint32 y = 0; y < bitmap->h; y++)
+                    {
+                        memcpy(dst, src, bitmap->w);
+                        src += bitmap->pitch;
+                        dst += bitmap->w;
+                    }
+                }
+                else
+                {
+                    for (sint32 y = 0; y < bitmap->h; y++)
+                    {
+                        for (sint32 x = 0; x < bitmap->w; x++)
+                        {
+                            memcpy(dst, src, 3);
+                            src += 3;
+                            dst += 4;
+                        }
+                        src += bitmap->pitch - (bitmap->w * 3);
+                    }
+                }
+                SDL_UnlockSurface(bitmap);
+            }
+            else
+            {
+                return false;
+            }
+            SDL_FreeSurface(bitmap);
+            return true;
+        }
+        else
+        {
+            log_warning("Failed to load bitmap: %s", SDL_GetError());
+            window_error_open(STR_HEIGHT_MAP_ERROR, STR_ERROR_READING_BITMAP);
+            return false;
+        }
+    }
+
+
 private:
     void OnResize(sint32 width, sint32 height)
     {

src/openrct2/Context.cpp

@@ -671,6 +671,11 @@ extern "C"
         windowManager->HandleKeyboard(isTitle);
     }
 
+    bool context_read_bmp(void * * outPixels, uint32 * outWidth, uint32 * outHeight, const utf8 * path)
+    {
+        return GetContext()->GetUiContext()->ReadBMP(outPixels, outWidth, outHeight, std::string(path));
+    }
+
     bool platform_open_common_file_dialog(utf8 * outFilename, file_dialog_desc * desc, size_t outSize)
     {
         try

src/openrct2/Context.h

@@ -129,6 +129,7 @@ extern "C"
     void context_set_cursor_trap(bool value);
     rct_window * context_open_window(rct_windowclass wc);
     void context_input_handle_keyboard(bool isTitle);
+    bool context_read_bmp(void * * outPixels, uint32 * outWidth, uint32 * outHeight, const utf8 * path);
 #ifdef __cplusplus
 }
 #endif

src/openrct2/ui/DummyUiContext.cpp

@@ -76,6 +76,9 @@ namespace OpenRCT2 { namespace Ui
         {
             return _windowManager;
         }
+
+        // Misc
+        bool ReadBMP(void * * outPixels, uint32 * outWidth, uint32 * outHeight, const std::string &path) override { return false; }
     };
 
     IUiContext * CreateDummyUiContext()

src/openrct2/ui/UiContext.h

@@ -131,6 +131,11 @@ namespace OpenRCT2
 
             // In-game UI
             virtual IWindowManager *    GetWindowManager() abstract;
+
+            // Misc.
+            // HACK: This should either be implemented ourselves in libopenrct2
+            //       or the mapgen height map code is moved to libopenrct2ui.
+            virtual bool                ReadBMP(void * * outPixels, uint32 * outWidth, uint32 * outHeight, const std::string &path) abstract;
         };
 
         IUiContext * CreateDummyUiContext();

src/openrct2/world/mapgen.c

@@ -16,7 +16,8 @@
 
 #include "../common.h"
 #include <math.h>
-#include <SDL.h>
+
+#include "../Context.h"
 #include "../Imaging.h"
 #include "../core/Guard.hpp"
 #include "../game.h"
@@ -805,31 +806,13 @@ bool mapgen_load_heightmap(const utf8 *path)
         pitch = width * numChannels;
     }
     else if (strcicmp(extension, ".bmp") == 0) {
-        SDL_Surface *bitmap = SDL_LoadBMP(path);
-        if (bitmap == NULL) {
-            log_warning("Failed to load bitmap: %s", SDL_GetError());
-            window_error_open(STR_HEIGHT_MAP_ERROR, STR_ERROR_READING_BITMAP);
+        if (!context_read_bmp((void *)&pixels, &width, &height, path)) {
+            // ReadBMP contains window_error_open calls
             return false;
         }
 
-        width = bitmap->w;
-        height = bitmap->h;
-        numChannels = bitmap->format->BytesPerPixel;
-        pitch = bitmap->pitch;
-
-        if (numChannels < 3 || bitmap->format->BitsPerPixel < 24)
-        {
-            window_error_open(STR_HEIGHT_MAP_ERROR, STR_ERROR_24_BIT_BITMAP);
-            SDL_FreeSurface(bitmap);
-            return false;
-        }
-
-        // Copy pixels over, then discard the surface
-        SDL_LockSurface(bitmap);
-        pixels = malloc(height * bitmap->pitch);
-        memcpy(pixels, bitmap->pixels, height * bitmap->pitch);
-        SDL_UnlockSurface(bitmap);
-        SDL_FreeSurface(bitmap);
+        numChannels = 4;
+        pitch = width * numChannels;
     }
     else
     {