modified text rendering algorithm, optimized charset files, fixed workflow error

.github/workflows/c-cpp.yml

@@ -12,6 +12,10 @@ jobs:
     runs-on: ubuntu-latest
 
     steps:
+    - name: Install SDL2 dependencies
+      run: |
+        sudo apt-get install -y libsdl2-dev
+
     - uses: actions/checkout@v4
     - name: make build
       run: make build

assets/compile_charsets.py

@@ -12,14 +12,14 @@ def compile_charset(filename):
 
     for row in range(8):
         for col in range(12):
-            out += "\n    { "
+            # out += "\n    "
+            out += "{"
 
             for row1 in range(0, 16):
                 for col1 in range(0, 16):
-                    out += f"{color_to_num(bitmap[row * 16 + row1, col * 16 + col1])}, "
-                out += "\n      "
+                    out += f"{color_to_num(bitmap[row * 16 + row1, col * 16 + col1])},"
+                # out += "\n      "
 
-            out = out[:-2]
             out += "},"
 
     return out + "}"

src/graphics/sdl_error.h

@@ -14,7 +14,6 @@
 void G_error() {
     const char* error = SDL_GetError();
 
-    printf("what\n");
     printf("SDL error:\n%s\n", error);
 
     SDL_Quit();

src/graphics/sdl_graphics.h

@@ -29,17 +29,4 @@ void G_setDrawColor(uint32_t color) {
         G_error();
 }
 
-/**
- * Sets rendering scale such that the video memory takes up the whole window.
- */
-void G_strechScreen() {
-    int width, height;
-    SDL_GetWindowSize(G_SDLwindow, &width, &height);
-
-    float scaleX = (float)width / G_width;
-    float scaleY = (float)height / G_height;
-    if (SDL_RenderSetScale(G_SDLrenderer, scaleX, scaleY))
-        G_error();
-}
-
 #endif

src/graphics/sdl_text.h → src/graphics/sdl_videomem.h

@@ -3,28 +3,10 @@
 
 #include <graphics/sdl_graphics.h>
 #include <graphics/sdl_init.h>
+#include <string.h>
 
 SDL_Texture *G_videomem = NULL;
 
-// note: 16x16 charsets might not be ideal
-/**
- * Writes a character at the specified x and y offset (16 pixel increments).
- * 
- * @param c character index in charset (not ASCII value)
- * @param x x character position
- * @param y y character position
- * @param charset the charset to be used
- */
-void G_writeChar(char c, int x, int y, const char charset[][256]) {
-    for (int j = 0; j < 16; j++) {
-        for (int k = 0; k < 16; k++) {
-            G_setDrawColor(0x00FF00FF * charset[c][j + k * 16]);
-
-            G_setPixel(j + x * 16, k + y * 16);
-        }
-    }
-}
-
 /**
  * Creates a video memory texture.
  * 
@@ -40,7 +22,7 @@ int G_initVideomem(int w, int h) {
     G_width = w;
     G_height = h;
 
-    G_videomem = SDL_CreateTexture(G_SDLrenderer, SDL_PIXELFORMAT_RGB888, SDL_TEXTUREACCESS_TARGET, w, h);
+    G_videomem = SDL_CreateTexture(G_SDLrenderer, SDL_PIXELFORMAT_ABGR32, SDL_TEXTUREACCESS_STREAMING, w, h);
 
     if (!G_videomem) {
         printf("failed to initialize video memory\n");
@@ -50,21 +32,6 @@ int G_initVideomem(int w, int h) {
     return 0;
 }
 
-/**
- * Sets the video memory as a render target.
- * 
- * @return `0` on success, `1` if video memory doesn't exist. Calls `G_error` on error.
- */
-int G_useVideomem() {
-    if (!G_videomem)
-        return 1;
-
-    if (SDL_SetRenderTarget(G_SDLrenderer, G_videomem))
-        G_error();
-
-    return 0;
-}
-
 /**
  * Renders the video memory.
  * 
@@ -76,17 +43,6 @@ int G_render() {
     if (!G_videomem)
         return 1;
 
-    // Update screen
-    G_strechScreen();
-
-    if (SDL_RenderCopy(G_SDLrenderer, G_videomem, NULL, NULL))
-        G_error();
-
-    SDL_RenderPresent(G_SDLrenderer);
-
-    if (SDL_SetRenderTarget(G_SDLrenderer, NULL))
-        G_error();
-
     // Draw video mem
     if (SDL_RenderCopy(G_SDLrenderer, G_videomem, NULL, NULL))
         G_error();
@@ -109,4 +65,31 @@ void G_deleteVideomem() {
     G_videomem = NULL;
 }
 
+// note: 16x16 charsets might not be ideal
+/**
+ * Writes a character at the specified x and y offset (16 pixel increments).
+ * 
+ * @param x x character position
+ * @param y y character position
+ * @param c character entry in charset
+ * @param color RGBA color of character
+ */
+void G_writeChar(int x, int y, const char c[256], Uint32 color) {
+    SDL_Rect rect = { x * 16, y * 16, 16, 16 };
+
+    char *pixels;
+    int pitch;
+
+    if (SDL_LockTexture(G_videomem, &rect, (void**)&pixels, &pitch))
+        G_error();
+
+    for (int y = 0; y < 16; y++) {
+        for (int x = 0; x < 16; x++) {
+            *(Uint32*)(pixels + x*4 + y*pitch) = color * c[x + y * 16];
+        }  
+    }
+
+    SDL_UnlockTexture(G_videomem);
+}
+
 #endif

src/main.c

@@ -1,11 +1,12 @@
 #include "graphics/sdl_init.h"
 #include "graphics/sdl_graphics.h"
 #include "graphics/sdl_error.h"
-#include "graphics/sdl_text.h"
+#include "graphics/sdl_videomem.h"
 #include "charset_debug.c"
 #include "charset.c"
 
 #include <stdlib.h>
+#include <string.h>
 
 void quit() {
     // Delete video memory
@@ -33,14 +34,11 @@ int main(int argc, char *argv[]) {
 
     // example sdl code
     G_initVideomem(640, 480);
-    G_useVideomem();
-
-    G_setDrawColor(0x00FF00FF);
 
     int xOffset = 0, yOffset = 0; 
 
     for (int i = 0; i < 96; i++) {
-        G_writeChar(i, xOffset, yOffset, charset);
+        G_writeChar(xOffset, yOffset, charset[i], 0x00FF00FF);
 
         if (xOffset++ == 39) {
             xOffset = 0;
@@ -52,7 +50,7 @@ int main(int argc, char *argv[]) {
     xOffset = 0;
 
     for (int i = 0; i < 96; i++) {
-        G_writeChar(i, xOffset, yOffset, charset_debug);
+        G_writeChar(xOffset, yOffset, charset_debug[i], 0x00FF00FF);
 
         if (xOffset++ == 39) {
             xOffset = 0;