Adds overridable Bitmap.contentEquals and Bitmap.contentHashCode to a…

…ll Bitmap implementations (#1730)

korim/src/commonMain/kotlin/korlibs/image/bitmap/Bitmap.kt

@@ -1,10 +1,6 @@
 package korlibs.image.bitmap
 
 import korlibs.datastructure.*
-import korlibs.memory.clamp
-import korlibs.memory.fract
-import korlibs.memory.toIntCeil
-import korlibs.memory.toIntFloor
 import korlibs.image.color.Colors
 import korlibs.image.color.RGBA
 import korlibs.image.color.RGBAPremultiplied
@@ -16,6 +12,7 @@ import korlibs.image.vector.Context2d
 import korlibs.io.lang.invalidOp
 import korlibs.math.geom.*
 import korlibs.math.interpolation.*
+import korlibs.memory.*
 import kotlin.math.min
 
 abstract class Bitmap(
@@ -286,7 +283,7 @@ abstract class Bitmap(
 
     fun toBMP32IfRequired(): Bitmap32 = if (this is Bitmap32) this else this.toBMP32()
 
-    fun contentEquals(other: Bitmap): Boolean {
+    open fun contentEquals(other: Bitmap): Boolean {
         if (this.width != other.width) return false
         if (this.height != other.height) return false
         for (y in 0 until height) for (x in 0 until width) {
@@ -295,6 +292,16 @@ abstract class Bitmap(
         return true
     }
 
+    open fun contentHashCode(): Int {
+        var v = 0
+        for (y in 0 until height) {
+            for (x in 0 until width) {
+                v += this.getRgbaRaw(x, y).value.hashCode() * (7 + x + y * 3)
+            }
+        }
+        return (width * 31 + height) + v + premultiplied.toInt()
+    }
+
     open fun clone(): Bitmap {
         val out = createWithThisFormat(width, height)
         copyUnchecked(0, 0, out, 0, 0, width, height)

korim/src/commonMain/kotlin/korlibs/image/bitmap/Bitmap16.kt

@@ -1,12 +1,12 @@
 package korlibs.image.bitmap
 
-import korlibs.memory.arraycopy
 import korlibs.image.color.ColorFormat
 import korlibs.image.color.RGBA
 import korlibs.image.color.RGBA_4444
 import korlibs.image.color.packRGBA
 import korlibs.image.color.unpackToRGBA
 import korlibs.io.lang.assert
+import korlibs.memory.*
 
 class Bitmap16(
     width: Int,
@@ -42,5 +42,8 @@ class Bitmap16(
         }
 	}
 
-	override fun toString(): String = "Bitmap16($width, $height, format=$format)"
+    override fun contentEquals(other: Bitmap): Boolean = (other is Bitmap16) && (this.width == other.width) && (this.height == other.height) && data.contentEquals(other.data)
+    override fun contentHashCode(): Int = (width * 31 + height) + data.contentHashCode() + premultiplied.toInt()
+
+    override fun toString(): String = "Bitmap16($width, $height, format=$format)"
 }

korim/src/commonMain/kotlin/korlibs/image/bitmap/Bitmap32.kt

@@ -389,8 +389,8 @@ class Bitmap32(
 	fun yCbCrToRgba(): Bitmap32 = clone().apply { yCbCrToRgbaInline() }
     fun yCbCrToRgbaInline() = updateColors { YCbCr(it.value).toRGBA() }
 
-    fun contentEquals(other: Any?): Boolean = (other is Bitmap32) && (this.width == other.width) && (this.height == other.height) && ints.contentEquals(other.ints)
-    fun contentHashCode(): Int = (width * 31 + height) + ints.contentHashCode() + premultiplied.toInt()
+    override fun contentEquals(other: Bitmap): Boolean = (other is Bitmap32) && (this.width == other.width) && (this.height == other.height) && ints.contentEquals(other.ints)
+    override fun contentHashCode(): Int = (width * 31 + height) + ints.contentHashCode() + premultiplied.toInt()
 
     // @TODO: Can't do this or won't be able to put Bitmaps on hashmaps
     //override fun equals(other: Any?): Boolean = (other is Bitmap32) && (this.width == other.width) && (this.height == other.height) && data.ints.contentEquals(other.data.ints)

korim/src/commonMain/kotlin/korlibs/image/bitmap/BitmapIndexed.kt

@@ -1,12 +1,8 @@
 package korlibs.image.bitmap
 
-import korlibs.memory.UByteArrayInt
-import korlibs.memory.arraycopy
-import korlibs.memory.extract
-import korlibs.memory.ilog2
-import korlibs.memory.insert
 import korlibs.image.color.RGBA
 import korlibs.image.color.RgbaArray
+import korlibs.memory.*
 import kotlin.math.max
 
 abstract class BitmapIndexed(
@@ -103,7 +99,10 @@ abstract class BitmapIndexed(
         return maxRefColor + 1
     }
 
-	override fun toBMP32(): Bitmap32 = Bitmap32(width, height, premultiplied = premultiplied).also { outBmp ->
+    override fun contentEquals(other: Bitmap): Boolean = (other is BitmapIndexed) && (this.width == other.width) && (this.height == other.height) && data.contentEquals(other.data)
+    override fun contentHashCode(): Int = (width * 31 + height) + data.contentHashCode() + premultiplied.toInt()
+
+    override fun toBMP32(): Bitmap32 = Bitmap32(width, height, premultiplied = premultiplied).also { outBmp ->
         val out = outBmp.ints
         val pal = this@BitmapIndexed.palette.ints
         for (n in 0 until area) out[n] = pal[getIntIndex(n)]

korim/src/commonMain/kotlin/korlibs/image/bitmap/FloatBitmap32.kt

@@ -122,6 +122,9 @@ class FloatBitmap32(
         }
     }
 
+    override fun contentEquals(other: Bitmap): Boolean = (other is FloatBitmap32) && (this.width == other.width) && (this.height == other.height) && data.contentEquals(other.data)
+    override fun contentHashCode(): Int = (width * 31 + height) + data.contentHashCode() + premultiplied.toInt()
+
     inline fun updateComponent(block: (component: Int, value: Float) -> Float): Unit {
         forEach { n, x, y ->
             setRgbaf(

korim/src/commonMain/kotlin/korlibs/image/bitmap/NativeImage.kt

@@ -61,6 +61,9 @@ abstract class NativeImage(width: Int, height: Int, val data: Any?, premultiplie
         writePixelsUnsafe(x0, 0, 1, height, tempInts, width)
     }
 
+    override fun contentEquals(other: Bitmap): Boolean = toBMP32().contentEquals(other)
+    override fun contentHashCode(): Int = toBMP32().contentHashCode()
+
     override fun createWithThisFormat(width: Int, height: Int): Bitmap = NativeImage(width, height)
     override fun toString(): String = "$name($width, $height)"
 }