...Actually add the SDL_Surface renderer file

src/Backends/Rendering/SDLSurface.cpp

@@ -0,0 +1,155 @@
+#include "../Rendering.h"
+
+#include <stddef.h>
+#include <stdlib.h>
+
+#include "SDL.h"
+
+#include "../../WindowsWrapper.h"
+
+#include "../../Font.h"
+
+typedef struct Backend_Surface
+{
+	SDL_Surface *sdl_surface;
+} Backend_Surface;
+
+static SDL_Window *window;
+static SDL_Surface *window_surface;
+
+static Backend_Surface framebuffer;
+
+static void RectToSDLRect(const RECT *rect, SDL_Rect *sdl_rect)
+{
+	sdl_rect->x = (int)rect->left;
+	sdl_rect->y = (int)rect->top;
+	sdl_rect->w = (int)(rect->right - rect->left);
+	sdl_rect->h = (int)(rect->bottom - rect->top);
+
+	if (sdl_rect->w < 0)
+		sdl_rect->w = 0;
+
+	if (sdl_rect->h < 0)
+		sdl_rect->h = 0;
+}
+
+BOOL Backend_Init(SDL_Window *p_window)
+{
+	window = p_window;
+
+	window_surface = SDL_GetWindowSurface(window);
+
+	framebuffer.sdl_surface = SDL_CreateRGBSurfaceWithFormat(0, window_surface->w, window_surface->h, 0, SDL_PIXELFORMAT_RGB24);
+
+	if (framebuffer.sdl_surface == NULL)
+		return FALSE;
+
+	return TRUE;
+}
+
+void Backend_Deinit(void)
+{
+	SDL_FreeSurface(framebuffer.sdl_surface);
+}
+
+void Backend_DrawScreen(void)
+{
+	SDL_BlitSurface(framebuffer.sdl_surface, NULL, window_surface, NULL);
+	SDL_UpdateWindowSurface(window);
+}
+
+Backend_Surface* Backend_CreateSurface(unsigned int width, unsigned int height)
+{
+	Backend_Surface *surface = (Backend_Surface*)malloc(sizeof(Backend_Surface));
+
+	if (surface == NULL)
+		return NULL;
+
+	surface->sdl_surface = SDL_CreateRGBSurfaceWithFormat(0, width, height, 0, SDL_PIXELFORMAT_RGB24);
+
+	if (surface->sdl_surface == NULL)
+	{
+		free(surface);
+		return NULL;
+	}
+
+	return surface;
+}
+
+void Backend_FreeSurface(Backend_Surface *surface)
+{
+	SDL_FreeSurface(surface->sdl_surface);
+	free(surface);
+}
+
+void Backend_LoadPixels(Backend_Surface *surface, const unsigned char *pixels, unsigned int width, unsigned int height, unsigned int pitch)
+{
+	for (unsigned int i = 0; i < height; ++i)
+	{
+		const unsigned char *src_row = &pixels[i * pitch];
+		unsigned char *dst_row = (unsigned char*)surface->sdl_surface->pixels + i * surface->sdl_surface->pitch;
+
+		memcpy(dst_row, src_row, width * 3);
+	}
+}
+
+void Backend_Blit(Backend_Surface *source_surface, const RECT *rect, Backend_Surface *destination_surface, long x, long y, BOOL colour_key)
+{
+	SDL_Rect source_rect;
+	RectToSDLRect(rect, &source_rect);
+
+	SDL_Rect destination_rect;
+	destination_rect.x = x;
+	destination_rect.y = y;
+	destination_rect.w = source_rect.w;
+	destination_rect.h = source_rect.h;
+
+	SDL_SetColorKey(source_surface->sdl_surface, colour_key ? SDL_TRUE : SDL_FALSE, SDL_MapRGB(source_surface->sdl_surface->format, 0, 0, 0)); // Assumes the colour key will always be #000000 (black)
+
+	SDL_BlitSurface(source_surface->sdl_surface, &source_rect, destination_surface->sdl_surface, &destination_rect);
+}
+
+void Backend_BlitToScreen(Backend_Surface *source_surface, const RECT *rect, long x, long y, BOOL colour_key)
+{
+	Backend_Blit(source_surface, rect, &framebuffer, x, y, colour_key);
+}
+
+void Backend_ColourFill(Backend_Surface *surface, const RECT *rect, unsigned char red, unsigned char green, unsigned char blue)
+{
+	SDL_Rect destination_rect;
+	RectToSDLRect(rect, &destination_rect);
+
+	SDL_FillRect(surface->sdl_surface, &destination_rect, SDL_MapRGB(surface->sdl_surface->format, red, green, blue));
+}
+
+void Backend_ColourFillToScreen(const RECT *rect, unsigned char red, unsigned char green, unsigned char blue)
+{
+	Backend_ColourFill(&framebuffer, rect, red, green, blue);
+}
+
+void Backend_ScreenToSurface(Backend_Surface *surface, const RECT *rect)
+{
+	Backend_Blit(&framebuffer, rect, surface, rect->left, rect->top, FALSE);
+}
+
+void Backend_DrawText(Backend_Surface *surface, FontObject *font, int x, int y, const char *text, unsigned long colour)
+{
+	DrawText(font, (unsigned char*)surface->sdl_surface->pixels, surface->sdl_surface->pitch, surface->sdl_surface->w, surface->sdl_surface->h, x, y, colour, text, strlen(text));
+}
+
+void Backend_DrawTextToScreen(FontObject *font, int x, int y, const char *text, unsigned long colour)
+{
+	Backend_DrawText(&framebuffer, font, x, y, text, colour);
+}
+
+void Backend_HandleDeviceLoss(void)
+{
+	// No problem for us
+}
+
+void Backend_HandleWindowResize(void)
+{
+	// https://wiki.libsdl.org/SDL_GetWindowSurface
+	// We need to fetch a new surface pointer
+	window_surface = SDL_GetWindowSurface(window);
+}