feat(main): floor and ceiling cast

main.go

@@ -110,8 +110,48 @@ func main() {
 			}
 		}
 
-		for i := range pixels {
-			pixels[i] = 0x00000000 // Set background to black
+		// Floorcasting logic
+		for y := 0; y < screenHeight; y += screenScale {
+			rayDirX0 := dirX - planeX
+			rayDirY0 := dirY - planeY
+			rayDirX1 := dirX + planeX
+			rayDirY1 := dirY + planeY
+
+			p := y - screenHeight/2
+			if p == 0 {
+				continue // avoid division by zero
+			}
+
+			posZ := 0.5 * float64(screenHeight)
+			rowDistance := posZ / float64(p)
+
+			floorStepX := rowDistance * (rayDirX1 - rayDirX0) / float64(screenWidth)
+			floorStepY := rowDistance * (rayDirY1 - rayDirY0) / float64(screenWidth)
+
+			floorX := posX + rowDistance*rayDirX0
+			floorY := posY + rowDistance*rayDirY0
+
+			for x := 0; x < screenWidth; x++ {
+				cellX := int(floorX)
+				cellY := int(floorY)
+
+				tx := int(float64(texWidth)*(floorX-float64(cellX))) & (texWidth - 1)
+				ty := int(float64(texHeight)*(floorY-float64(cellY))) & (texHeight - 1)
+
+				floorX += floorStepX
+				floorY += floorStepY
+
+				floorTexture := 3
+				ceilingTexture := 6
+
+				var color uint32 = textures[floorTexture][texWidth*ty+tx]
+				color = (color >> 1) & 0x7F7F7F // darken
+				pixels[y*screenWidth+x] = color
+
+				color = textures[ceilingTexture][texWidth*ty+tx]
+				color = (color >> 1) & 0x7F7F7F
+				pixels[(screenHeight-y-1)*screenWidth+x] = color
+			}
 		}
 
 		// Raycasting logic