Render textg

src/dusk/display/renderbase.c

@@ -6,5 +6,3 @@
  */
 
 #include "display/render.h"
-
-uint8_t RENDER_FRAME = 0;

src/dusk/display/renderbase.h

@@ -15,8 +15,6 @@
   #define RENDER_HEIGHT 240
 #endif
 
-extern uint8_t RENDER_FRAME;
-
 /**
  * Initializes the rendering system.
  */

src/dusksdl2/display/CMakeLists.txt

@@ -7,6 +7,8 @@
 target_sources(${DUSK_TARGET_NAME}
   PRIVATE
     render.c
+    renderbackbuffer.c
+    rendertext.c
 )
 
 # Subdirs

src/dusksdl2/display/render.c

@@ -7,12 +7,15 @@
 
 #include "render.h"
 #include "assert/assert.h"
+#include "renderbackbuffer.h"
+#include "rendertext.h"
 
 SDL_Window *RENDER_WINDOW;
 SDL_Renderer *RENDER_RENDERER;
 bool_t RENDER_RUNNING;
 
 errorret_t renderInit(void) {
+  // Init SDL
   if(SDL_Init(SDL_INIT_VIDEO) != 0) {
     errorThrow(
       "SDL Failed to Initialize: %s",
@@ -20,31 +23,36 @@ errorret_t renderInit(void) {
     );
   }
 
+  // Create window.
   RENDER_WINDOW = SDL_CreateWindow(
     "DuskSDL2",
     SDL_WINDOWPOS_UNDEFINED,
     SDL_WINDOWPOS_UNDEFINED,
     RENDER_WINDOW_WIDTH_DEFAULT,
     RENDER_WINDOW_HEIGHT_DEFAULT,
-    SDL_WINDOW_SHOWN
+    SDL_WINDOW_SHOWN | SDL_WINDOW_RESIZABLE | SDL_WINDOW_ALLOW_HIGHDPI
   );
+  if(!RENDER_WINDOW) {
+    errorThrow("SDL_CreateWindow failed: %s", SDL_GetError());
+  }
 
-  #if RENDER_USE_FRAMEBUFFER
-    printf("Using framebuffer for rendering\n");
-  #else
-    printf("Using window for rendering\n");
-  #endif
-
+  // Create renderer
   RENDER_RENDERER = SDL_CreateRenderer(
     RENDER_WINDOW,
     -1,
     SDL_RENDERER_ACCELERATED
   );
-
   if(!RENDER_RENDERER) {
     errorThrow("SDL_CreateRenderer failed: %s", SDL_GetError());
   }
 
+  // Create back buffer.
+  renderBackBufferInit();
+  
+  // Init other things
+  renderTextInit();
+  
+  // Mark ready.
   RENDER_RUNNING = true;
 
   errorOk();
@@ -58,23 +66,27 @@ errorret_t renderDraw(void) {
     }
   }
 
-  SDL_SetRenderDrawColor(RENDER_RENDERER, 0, 0, 0, 255);
-  SDL_RenderClear(RENDER_RENDERER);
+  // Bind the backbuffer
+  renderBackBufferBind();
 
-  // Draw red triangle
-  SDL_SetRenderDrawColor(RENDER_RENDERER, 255, 0, 0, 255);
-  SDL_RenderDrawLine(RENDER_RENDERER, 100, 100, 200, 100);
-  SDL_RenderDrawLine(RENDER_RENDERER, 200, 100, 150, 50);
-  SDL_RenderDrawLine(RENDER_RENDERER, 150, 50, 100, 100);
+  // Draw everything
+  renderTextDraw(0.0f, 0.0f, "Hello World!");
 
+  // Unbind the backbuffer
+  renderBackBufferUnbind();
+  renderBackBufferDraw();
+
+  // Draw things that render above the back buffer quad.
+
+  // Present the renderer
   SDL_RenderPresent(RENDER_RENDERER);
 
-  RENDER_FRAME++;
-
   errorOk();
 }
 
 errorret_t renderDispose(void) {
+  renderBackBufferDispose();
+
   SDL_DestroyRenderer(RENDER_RENDERER);
   SDL_DestroyWindow(RENDER_WINDOW);
   SDL_Quit();

src/dusksdl2/display/renderbackbuffer.c

@@ -6,6 +6,7 @@
  */
 
 #include "renderbackbuffer.h"
+#include "render.h"
 
 #if RENDER_USE_FRAMEBUFFER
   SDL_Texture *RENDER_BACKBUFFER;
@@ -13,23 +14,81 @@ SDL_Texture *RENDER_BACKBUFFER;
 
 #endif
 
-void renderBackBufferInit(void) {
+errorret_t renderBackBufferInit(void) {
   #if RENDER_USE_FRAMEBUFFER
     RENDER_BACKBUFFER = SDL_CreateTexture(
       RENDER_RENDERER,
       SDL_PIXELFORMAT_RGBA8888,
       SDL_TEXTUREACCESS_TARGET,
-      RENDER_WINDOW_WIDTH_DEFAULT,
-      RENDER_WINDOW_HEIGHT_DEFAULT
+      RENDER_WIDTH,
+      RENDER_HEIGHT
     );
 
     if(!RENDER_BACKBUFFER) {
-      assertUnreachable("SDL_CreateTexture failed\n");
-      return;
+      errorThrow("SDL_CreateTexture failed: %s", SDL_GetError());
     }
+
+    // Make sure we unbind the back buffer after creation
+    SDL_SetRenderTarget(RENDER_RENDERER, NULL);
   #else
     // No back buffer needed for window rendering
   #endif
 
-  
+  errorOk();
+}
+
+void renderBackBufferBind(void) {
+  #if RENDER_USE_FRAMEBUFFER
+    SDL_SetRenderTarget(RENDER_RENDERER, RENDER_BACKBUFFER);
+  #endif
+  
+  // Fill background with cornflower blue.
+  SDL_SetRenderDrawColor(RENDER_RENDERER, 100, 149, 237, 255);
+  SDL_RenderClear(RENDER_RENDERER);
+}
+
+void renderBackBufferUnbind(void) {
+  #if RENDER_USE_FRAMEBUFFER
+    SDL_SetRenderTarget(RENDER_RENDERER, NULL);
+  #endif
+}
+
+void renderBackBufferDraw(void) {
+  #if RENDER_USE_FRAMEBUFFER
+    // Clear background black
+    SDL_SetRenderDrawColor(RENDER_RENDERER, 0, 0, 0, 255);
+    SDL_RenderClear(RENDER_RENDERER);
+
+    // Create a quad that is scaled to fit but maintain original aspect ratio
+    int32_t windowWidth, windowHeight;
+    SDL_GetWindowSize(RENDER_WINDOW, &windowWidth, &windowHeight);
+
+    int32_t renderWidth, renderHeight, renderX, renderY;
+    if(RENDER_WIDTH * windowHeight > RENDER_HEIGHT * windowWidth) {
+      renderWidth = windowWidth;
+      renderHeight = (RENDER_HEIGHT * windowWidth) / RENDER_WIDTH;
+      renderX = 0;
+      renderY = (windowHeight - renderHeight) / 2;
+    } else {
+      renderWidth = (RENDER_WIDTH * windowHeight) / RENDER_HEIGHT;
+      renderHeight = windowHeight;
+      renderX = (windowWidth - renderWidth) / 2;
+      renderY = 0;
+    }
+
+    // Draw the back buffer texture
+    SDL_Rect destRect = { renderX, renderY, renderWidth, renderHeight };
+    SDL_RenderCopy(RENDER_RENDERER, RENDER_BACKBUFFER, NULL, &destRect);
+  #else
+    // No back buffer to draw
+  #endif
+}
+
+errorret_t renderBackBufferDispose(void) {
+  #if RENDER_USE_FRAMEBUFFER
+    SDL_DestroyTexture(RENDER_BACKBUFFER);
+    RENDER_BACKBUFFER = NULL;
+  #endif
+
+  errorOk();
 }

src/dusksdl2/display/renderbackbuffer.h

@@ -6,4 +6,32 @@
  */
 
 #pragma once
-#include "dusksdl2.h"
+#include "display/renderbase.h"
+
+/**
+ * Initializes the render back buffer. May be either a framebuffer or a texture
+ * depending on the render settings.
+ */
+errorret_t renderBackBufferInit(void);
+
+/**
+ * Binds the render back buffer as the current render target.
+ */
+void renderBackBufferBind(void);
+
+/**
+ * Unbinds the render back buffer, returning to the default render target.
+ */
+void renderBackBufferUnbind(void);
+
+/**
+ * Draws the render back buffer to the screen, scaling it to fit the window.
+ */
+void renderBackBufferDraw(void);
+
+/**
+ * Disposes of the render back buffer, freeing any resources it holds.
+ * 
+ * @return An error state if an error occurred, otherwise OK.
+ */
+errorret_t renderBackBufferDispose(void);

src/dusksdl2/display/rendertext.c

@@ -0,0 +1,113 @@
+/**
+ * Copyright (c) 2025 Dominic Masters
+ * 
+ * This software is released under the MIT License.
+ * https://opensource.org/licenses/MIT
+ */
+
+#include "rendertext.h"
+#include "render.h"
+#include "ui/font.h"
+#include "assert/assert.h"
+
+SDL_Texture* RENDER_TEXT_TEXTURE = NULL;
+
+void renderTextInit(void) {
+  const int32_t cols = FONT_COLUMN_COUNT;
+  const int32_t rows = (FONT_TILE_COUNT + cols - 1) / cols;
+  const int32_t fontWidth  = cols * FONT_TILE_WIDTH;
+  const int32_t fontHeight = rows * FONT_TILE_HEIGHT;
+
+  // RGBA8888 surface
+  SDL_Surface* surface = SDL_CreateRGBSurfaceWithFormat(
+    0,
+    fontWidth,
+    fontHeight,
+    32,
+    SDL_PIXELFORMAT_RGBA32
+  );
+  assertNotNull(surface, "Failed to create surface for text rendering");
+
+  const int32_t pitch_px = surface->pitch / 4;
+  uint32_t *pixels = (uint32_t *)surface->pixels;
+
+  for(int tileIndex = 0; tileIndex < FONT_TILE_COUNT; ++tileIndex) {
+    const int32_t tileX = (tileIndex % FONT_COLUMN_COUNT) * FONT_TILE_WIDTH;
+    const int32_t tileY = (tileIndex / FONT_COLUMN_COUNT) * FONT_TILE_HEIGHT;
+    const uint8_t* tile = TILE_PIXEL_DATA[tileIndex];
+
+    for (int y = 0; y < FONT_TILE_HEIGHT; ++y) {
+      for (int x = 0; x < FONT_TILE_WIDTH; ++x) {
+        const uint8_t color = tile[y * FONT_TILE_WIDTH + x] ? 0xFF : 0;
+        // Convert to RGBA (8 bits per channel)
+        const uint32_t rgba = color ? 0xFFFFFFFF : 0x00000000;
+        pixels[(tileY + y) * pitch_px + (tileX + x)] = rgba;
+      }
+    }
+  }
+
+  RENDER_TEXT_TEXTURE = SDL_CreateTextureFromSurface(
+    RENDER_RENDERER,
+    surface
+  );
+  assertNotNull(RENDER_TEXT_TEXTURE, "Failed to create texture from surface");
+
+  SDL_FreeSurface(surface);
+  SDL_SetTextureBlendMode(RENDER_TEXT_TEXTURE, SDL_BLENDMODE_BLEND);
+}
+
+void renderTextDrawChar(
+  const float_t x,
+  const float_t y,
+  const char_t c
+) {
+  int32_t tileIndex = (int32_t)(c) - FONT_CHAR_START;
+
+  assertTrue(
+    tileIndex >= 0 && tileIndex < FONT_TILE_COUNT, 
+    "Character is out of bounds for font tiles"
+  );
+  assertNotNull(RENDER_TEXT_TEXTURE, "Texture cannot be NULL");
+  
+  const int32_t tileX = (tileIndex % FONT_COLUMN_COUNT) * FONT_TILE_WIDTH;
+  const int32_t tileY = (tileIndex / FONT_COLUMN_COUNT) * FONT_TILE_HEIGHT;
+
+  SDL_Rect srcRect = {
+    .x = tileX,
+    .y = tileY,
+    .w = FONT_TILE_WIDTH,
+    .h = FONT_TILE_HEIGHT
+  };
+
+  SDL_Rect dstRect = {
+    .x = (int32_t)roundf(x),
+    .y = (int32_t)roundf(y),
+    .w = FONT_TILE_WIDTH,
+    .h = FONT_TILE_HEIGHT
+  };
+  SDL_RenderCopy(RENDER_RENDERER, RENDER_TEXT_TEXTURE, &srcRect, &dstRect);
+}
+
+void renderTextDraw(
+  const float_t x,
+  const float_t y,
+  const char_t *text
+) {
+  assertNotNull(text, "Text cannot be NULL");
+  
+  float_t posX = x;
+  float_t posY = y;
+
+  char_t c;
+  int32_t i = 0;
+  while((c = text[i++]) != '\0') {
+    if(c == '\n') {
+      posX = x;
+      posY += FONT_TILE_HEIGHT;
+      continue;
+    }
+
+    renderTextDrawChar(posX, posY, c);
+    posX += FONT_TILE_WIDTH;
+  }
+}

src/dusksdl2/display/rendertext.h

@@ -0,0 +1,42 @@
+/**
+ * Copyright (c) 2025 Dominic Masters
+ * 
+ * This software is released under the MIT License.
+ * https://opensource.org/licenses/MIT
+ */
+
+#pragma once
+#include "dusksdl2.h"
+
+extern SDL_Texture* RENDER_TEXT_TEXTURE;
+
+/**
+ * Initializes the text rendering system.
+ */
+void renderTextInit(void);
+
+/**
+ * Draws a single character at the specified position.
+ * 
+ * @param x The x-coordinate to draw the character at.
+ * @param y The y-coordinate to draw the character at.
+ * @param c The character to draw.
+ */
+void renderTextDrawChar(
+  const float_t x,
+  const float_t y,
+  const char_t c
+);
+
+/**
+ * Draws a string of text at the specified position.
+ * 
+ * @param x The x-coordinate to draw the text at.
+ * @param y The y-coordinate to draw the text at.
+ * @param text The null-terminated string of text to draw.
+ */
+void renderTextDraw(
+  const float_t x,
+  const float_t y,
+  const char_t *text
+);