Merge pull request #449 from JD557/plane-optimizations

Avoid Plane allocation/indirection

core/shared/src/main/scala/eu/joaocosta/minart/graphics/Matrix.scala

@@ -20,13 +20,17 @@ final case class Matrix(a: Double, b: Double, c: Double, d: Double, e: Double, f
       this.d * that.c + this.e * that.f + this.f
     )
 
+  inline def applyX(x: Double, y: Double): Double = a * x + b * y + c * 1
+  inline def applyX(x: Int, y: Int): Int          = (a * x + b * y + c * 1).toInt
+  inline def applyY(x: Double, y: Double): Double = d * x + e * y + f * 1
+  inline def applyY(x: Int, y: Int): Int          = (d * x + e * y + f * 1).toInt
+
   /** Applies the transformation to (x, y). */
   def apply(x: Double, y: Double): (Double, Double) =
-    (a * x + b * y + c * 1, d * x + e * y + f * 1)
+    (applyX(x, y), applyY(x, y))
 
   /** Applies the transformation to (x, y). */
   def apply(x: Int, y: Int): (Int, Int) = {
-    val res = apply(x.toDouble, y.toDouble)
-    (res._1.toInt, res._2.toInt)
+    (applyX(x, y), applyY(x, y))
   }
 }

core/shared/src/main/scala/eu/joaocosta/minart/graphics/Plane.scala

@@ -68,7 +68,7 @@ trait Plane extends Function2[Int, Int, Color] { outer =>
     * @param cw clip width
     * @param ch clip height
     */
-  final def clip(cx: Int, cy: Int, cw: Int, ch: Int): SurfaceView =
+  def clip(cx: Int, cy: Int, cw: Int, ch: Int): SurfaceView =
     if (cx == 0 && cy == 0) toSurfaceView(cw, ch)
     else
       new Plane {
@@ -97,7 +97,7 @@ trait Plane extends Function2[Int, Int, Color] { outer =>
     }
 
   /** Inverts a plane color. */
-  def invertColor: Plane = map(_.invert)
+  final def invertColor: Plane = map(_.invert)
 
   /** Contramaps this plane using a matrix instead of a function.
     *
@@ -124,32 +124,41 @@ trait Plane extends Function2[Int, Int, Color] { outer =>
     Plane.MatrixPlane(matrix, this)
 
   /** Translates a plane. */
-  def translate(dx: Double, dy: Double): Plane = contramapMatrix(Matrix(1, 0, -dx, 0, 1, -dy))
+  final def translate(dx: Double, dy: Double): Plane =
+    if (dx == 0 && dy == 0) this
+    else contramapMatrix(Matrix(1, 0, -dx, 0, 1, -dy))
 
   /** Flips a plane horizontally. */
-  def flipH: Plane = contramapMatrix(Matrix(-1, 0, 0, 0, 1, 0))
+  final def flipH: Plane = contramapMatrix(Matrix(-1, 0, 0, 0, 1, 0))
 
   /** Flips a plane vertically. */
-  def flipV: Plane = contramapMatrix(Matrix(1, 0, 0, 0, -1, 0))
+  final def flipV: Plane = contramapMatrix(Matrix(1, 0, 0, 0, -1, 0))
 
   /** Scales a plane. */
-  def scale(sx: Double, sy: Double): Plane = contramapMatrix(Matrix(1.0 / sx, 0, 0, 0, 1.0 / sy, 0))
+  final def scale(sx: Double, sy: Double): Plane =
+    if (sx == 1.0 && sy == 1.0) this
+    else contramapMatrix(Matrix(1.0 / sx, 0, 0, 0, 1.0 / sy, 0))
 
   /** Scales a plane. */
-  def scale(s: Double): Plane = scale(s, s)
+  final def scale(s: Double): Plane = scale(s, s)
 
   /** Rotates a plane by a certain angle (clockwise). */
-  def rotate(theta: Double): Plane = {
+  final def rotate(theta: Double): Plane = {
     val ct = Math.cos(-theta)
-    val st = Math.sin(-theta)
-    contramapMatrix(Matrix(ct, -st, 0, st, ct, 0))
+    if (ct == 1.0) this
+    else {
+      val st = Math.sin(-theta)
+      contramapMatrix(Matrix(ct, -st, 0, st, ct, 0))
+    }
   }
 
   /** Shears a plane. */
-  def shear(sx: Double, sy: Double): Plane = contramapMatrix(Matrix(1.0, -sx, 0, -sy, 1.0, 0))
+  final def shear(sx: Double, sy: Double): Plane =
+    if (sx == 0.0 && sy == 0.0) this
+    else contramapMatrix(Matrix(1.0, -sx, 0, -sy, 1.0, 0))
 
   /** Transposes a plane (switches the x and y coordinates). */
-  def transpose: Plane = contramapMatrix(Matrix(0, 1, 0, 1, 0, 0))
+  final def transpose: Plane = contramapMatrix(Matrix(0, 1, 0, 1, 0, 0))
 
   /** Converts this plane to a surface view, assuming (0, 0) as the top-left corner.
     *
@@ -171,12 +180,14 @@ trait Plane extends Function2[Int, Int, Color] { outer =>
 object Plane {
   private[Plane] final case class MatrixPlane(matrix: Matrix, plane: Plane) extends Plane {
     def getPixel(x: Int, y: Int): Color = {
-      val (xx, yy) = matrix(x, y)
-      plane.getPixel(xx, yy)
+      plane.getPixel(matrix.applyX(x, y), matrix.applyY(x, y))
     }
 
     override def contramapMatrix(matrix: Matrix) =
       MatrixPlane(this.matrix.multiply(matrix), plane)
+
+    override def clip(cx: Int, cy: Int, cw: Int, ch: Int): SurfaceView =
+      translate(-cx, -cy).toSurfaceView(cw, ch)
   }
 
   /** Creates a plane from a constant color.

core/shared/src/main/scala/eu/joaocosta/minart/graphics/SurfaceView.scala

@@ -67,7 +67,7 @@ final case class SurfaceView(plane: Plane, width: Int, height: Int) extends Surf
     * @param x leftmost pixel on the destination plane
     * @param y topmost pixel on the destination plane
     */
-  final def overlay(that: Surface, blendMode: BlendMode = BlendMode.Copy)(x: Int, y: Int): SurfaceView =
+  def overlay(that: Surface, blendMode: BlendMode = BlendMode.Copy)(x: Int, y: Int): SurfaceView =
     copy(plane = plane.overlay(that, blendMode)(x, y))
 
   /** Inverts a surface color. */
@@ -90,7 +90,8 @@ final case class SurfaceView(plane: Plane, width: Int, height: Int) extends Surf
 
   /** Scales a surface. */
   def scale(sx: Double, sy: Double): SurfaceView =
-    copy(plane = plane.scale(sx, sy), width = (width * sx).toInt, height = (height * sy).toInt)
+    if (sx == 1.0 && sy == 1.0) this
+    else copy(plane = plane.scale(sx, sy), width = (width * sx).toInt, height = (height * sy).toInt)
 
   /** Scales a surface. */
   def scale(s: Double): SurfaceView = scale(s, s)