Floors

Signed-off-by: Hans Kokx <hans.d.kokx@gmail.com>

raycaster.c

@@ -859,6 +859,7 @@ void drawRays3D()
 
     int x, y;
     int textureX;
+    float textureY;
 
     if (shade == 1) // North-south walls (PI -> (2 * PI))
     {
@@ -880,7 +881,7 @@ void drawRays3D()
 
     for (x = xStart; x < xEnd; x++)
     {
-      float textureY = textureYoffset * textureYstep + (horizontalMapTexture * 32);
+      textureY = textureYoffset * textureYstep + (horizontalMapTexture * 32);
       for (y = 0; y < lineHeight; y++)
       {
         float c = All_Textures[((int)textureY * mapSize) + textureX] * shade;
@@ -918,6 +919,43 @@ void drawRays3D()
     {
       rayAngle -= 2 * PI;
     }
+
+    // * Draw Floors (camera-plane floor casting)
+    // The walls use angular rays, but floors need projection-plane directions
+    // where every column spans both world axes, so the vertical texture
+    // coordinate advances everywhere (no degenerate center column).
+    float planeLen = tanf(DR * 30.0f); // half-FOV for the 60-degree view
+    float planeX = -sin(playerAngle) * planeLen;
+    float planeY = cos(playerAngle) * planeLen;
+
+    for (x = xStart; x < xEnd; x++)
+    {
+      // Projection-plane offset for this screen column, in [-1, 1].
+      float cameraX = 2.0f * (x + 0.5f) / (float)gameWidth - 1.0f;
+      float rayDirX = cos(playerAngle) + planeX * cameraX;
+      float rayDirY = sin(playerAngle) + planeY * cameraX;
+
+      for (y = lineOffset + lineHeight; y < TOTAL_HEIGHT; y++)
+      {
+        // Vertical distance below the horizon; grows the closer to the player.
+        float dy = y - (TOTAL_HEIGHT / 2.0);
+
+        // Perspective: world distance along the ray to reach this screen row.
+        // Scaled by mapSize so one texture tile spans one map unit, matching the
+        // wall texture sampling.
+        float rowDistance = (gameHeight / 2.0) * mapSize / dy;
+
+        float fx = playerX + rowDistance * rayDirX;
+        float fy = playerY + rowDistance * rayDirY;
+
+        int tx = ((int)fx) & (mapSize - 1);
+        int ty = ((int)fy) & (mapSize - 1);
+
+        float c = All_Textures[(ty * mapSize) + tx] * 0.7;
+        glColor3f(c, c, c);
+        glVertex2i(MAP_WIDTH + GAP + x, (int)y);
+      }
+    }
   }
   glEnd();
 }