Start assets

TODO.txt

@@ -1,3 +1,9 @@
+- background sky rendering efficiently:
+  - first draw the solid color top and bottom
+  - then render the 3D scene
+  - then iterate over the strip that should have the sky texture and only draw
+    to pixels where depth buffer was not overwritten (this step can be left out
+    in case we have depth buffer or sky turned off)
 TOTAL SIZE OF TEXTURES:
   - 64 x 64 x 2 = 8192, 6 x floor + 2 x wall + 1 x car = 8 * 8192 = 73728
   - (128 x 128 x 1) x 3 background = 49152

assets.h

@@ -3,8 +3,7 @@
 
 #include <stdint.h>
 
-
+#define LCR_SKY_IMAGE_SIZE 128
-
 
 static const uint16_t LCR_skyImages[] =
 {

game.h

@@ -116,8 +116,43 @@ void LCR_gameEnd(void)
 {
 }
 
-void LCR_drawSky()
+void LCR_drawSkyStrip(int verticalOffset, uint8_t horizontalOffset)
 {
+
+#if LCR_SETTING_SKY_SIZE != 0
+
+  verticalOffset -= (LCR_SETTING_SKY_SIZE * LCR_SKY_IMAGE_SIZE) / 2; 
+
+  int finalY = verticalOffset + LCR_SETTING_SKY_SIZE * LCR_SKY_IMAGE_SIZE;
+
+  if (finalY >= LCR_EFFECTIVE_RESOLUTION_Y)
+    finalY = LCR_EFFECTIVE_RESOLUTION_Y - 1;
+
+  unsigned int skyY = 0;
+
+  if (verticalOffset < 0)
+  {
+    skyY = -1 * verticalOffset;
+    verticalOffset = 0;
+  }
+
+  while (verticalOffset < finalY)
+  {
+    for (int i = 0; i < LCR_EFFECTIVE_RESOLUTION_X; ++i)
+    {
+      LCR_drawPixelUnsafe(x,y,10000); 
+    }
+
+    skyY++;
+    verticalOffset++;
+  }
+
+#endif
+
+
+
+
+/*
   const uint16_t *pixel = LCR_skyImages + 256;
   uint8_t odd = 1;
 
@@ -138,6 +173,7 @@ void LCR_drawSky()
         pixel++;
       }
     }
+*/
 
 }
 
@@ -146,7 +182,7 @@ uint8_t LCR_gameStep(uint32_t time)
   for (int i = 0; i < LCR_KEYS_TOTAL; ++i)
     _LCR_keyStates[i] = LCR_keyPressed(i);
 
-  LCR_drawSky();
+  LCR_drawSkyStrip();
 
   return 1;
 }

settings.h

@@ -13,6 +13,11 @@
   #define LCR_SETTING_RESOLUTION_SUBDIVIDE 1
 #endif
 
+#ifndef LCR_SETTING_SKY_SIZE
+  /** Size of sky texture pixel, 0 turns off sky rendering. */
+  #define LCR_SETTING_SKY_SIZE 1
+#define
+
 #ifndef LCR_SETTING_MAP_MAX_SIZE
   /** Maximum number of blocks a map can consist of, decreasing will save RAM
     but also rule out loading bigger maps. */