Add support for negative coordinates on HeightMaps and Layers2D (#235)

* Add support for negative coordinates on HeightMaps and Layers2D

* Fix HeightMap tiles cache indexes

---------

Co-authored-by: Simon Rozec <[email protected]>

hrt/prefab/l3d/HeightMap.hx

@@ -477,7 +477,7 @@ class HeightMapMesh extends h3d.scene.Object {
 		var t = hmap.getTile(x,y);
 		if( !ctx.camera.frustum.hasBounds(t.bounds) || t.isEmpty() ) {
 			if( t.root != null ) t.root.visible = false;
-			return x >= 0 && y >= 0 && x < hmap.sizeX && y < hmap.sizeY;
+			return hmap.isTileInBounds(x, y);
 		}
 		if( t.root != null )
 			t.root.visible = true;
@@ -611,6 +611,8 @@ class HeightMap extends Object3D {
 	}
 	@:s var sizeX = 0;
 	@:s var sizeY = 0;
+	@:s var minTileX = 0;
+	@:s var minTileY = 0;
 	@:s var autoSize = false;
 	@:s var albedoTiling = 1.;
 	@:s var albedoGamma = 1.;
@@ -748,13 +750,17 @@ class HeightMap extends Object3D {
 		return -1;
 	}
 
+	public inline function isTileInBounds(x : Int, y : Int) {
+		return x >= minTileX && y >= minTileX && x < sizeX + minTileX && y < sizeY + minTileX;
+	}
+
 	function getTile( x : Int, y : Int ) {
-		if( (sizeX > 0 && sizeY > 0 && (x < 0 || y < 0 || x >= sizeX || y >= sizeY)) || (sizeX == 0 && sizeY == 0 && (x != 0 || y != 0) && !autoSize) ) {
+		if( (sizeX > 0 && sizeY > 0 && !isTileInBounds(x, y)) || (sizeX == 0 && sizeY == 0 && (x != 0 || y != 0) && !autoSize) ) {
 			if( emptyTile == null )
-				emptyTile = new HeightMapTile(this, -1, -1);
+				emptyTile = new HeightMapTile(this, -minTileX - 1, -minTileY - 1);
 			return emptyTile;
 		}
-		var id = x + y * 65535;
+		var id = x - minTileX + (y - minTileY) * 65535;
 		var t = tilesCache[id];
 		if( t != null )
 			return t;
@@ -1001,6 +1007,8 @@ class HeightMap extends Object3D {
 				<dt>Gamma</dt><dd><input type="range" min="0" max="4" field="albedoGamma"/></dd>
 				<dt>Gamma Color</dt><dd><input type="range" min="0" max="4" field="albedoColorGamma"/></dd>
 				<dt>Fixed Size</dt><dd><input type="number" style="width:50px" field="sizeX"/><input type="number" style="width:50px" field="sizeY"/> <label><input type="checkBox" field="autoSize"> Auto</label></dd>
+				<dt>Min Tile X</dt><dd><input type="range" min="-1000" max="0" field="minTileX"/></dd>
+				<dt>Min Tile Y</dt><dd><input type="range" min="-1000" max="0" field="minTileY"/></dd>
 				<dt>Bake Albedo</dt><dd><input type="checkbox" field="bakedAlbedo"/></dd>
 				<dt>Baked Albedo Size</dt><dd><input type="range" step="2" field="bakedAlbedoSize"/></dd>
 			</dl>

hrt/prefab/l3d/Layers2D.hx

@@ -17,6 +17,8 @@ class LayerView2DRFXShader extends h3d.shader.ScreenShader {
 
 		@param var layerAlpha : Float;
 		@param var worldSize : Float;
+		@param var offsetX : Float;
+		@param var offsetY : Float;
 
 		@param var collideMap : Sampler2D;
 		@const var collideEnable : Bool;
@@ -60,6 +62,8 @@ class LayerView2DRFXShader extends h3d.shader.ScreenShader {
 			pixelColor = curColor;
 
 			var curPos = getPixelPosition(calculatedUV).xy;
+			curPos.x -= offsetX;
+			curPos.y -= offsetY;
 
 			var collide = false;
 
@@ -142,6 +146,8 @@ class Layers2D extends hrt.prefab.Object3D {
 	@:s var collidePath : String;
 	@:s var collideMask : Int = 0xff0000;
 	@:s var worldSize : Int = 4096;
+	@:s var offsetX : Int = 0;
+	@:s var offsetY : Int = 0;
 	var layerTextures : Map<String, hxd.Pixels> = [];
 
 	@:s var highlightColor : Int = 0xff00ff;
@@ -235,8 +241,8 @@ class Layers2D extends hrt.prefab.Object3D {
 	public function getLayerColor( layer : hxd.Pixels, x : Float, y : Float ) {
 		if ( layer == null )
 			return -1;
-		var ix = Std.int(x / layerScale);
-		var iy = Std.int(y / layerScale);
+		var ix = Std.int( (x - offsetX) / layerScale);
+		var iy = Std.int( (y - offsetY) / layerScale);
 		if ( ix < 0 || ix > layer.width || iy < 0 || iy > layer.height )
 			return -1;
 
@@ -303,6 +309,8 @@ class Layers2D extends hrt.prefab.Object3D {
 
 			sh.layerAlpha = layerAlpha;
 			sh.worldSize = worldSize;
+			sh.offsetX = offsetX;
+			sh.offsetY = offsetY;
 			sh.collideScale = (collideMap != null) ? worldSize / collideMap.width : 1;
 			sh.collideMap = collideMap;
 
@@ -421,8 +429,8 @@ class Layers2D extends hrt.prefab.Object3D {
 			var collideScale = collidePixels.width / worldSize;
 
 			if ( worldPos != null ) {
-				var startX = worldPos.x;
-				var startY = worldPos.y;
+				var startX = worldPos.x - offsetX;
+				var startY = worldPos.y - offsetY;
 
 				var brRadius = ( clean ) ? eraseRadius : brushRadius;
 				var radiusSq = brRadius * brRadius;
@@ -643,6 +651,7 @@ class Layers2D extends hrt.prefab.Object3D {
 						<dl>
 							<dt>World Size</dt><dd><input type="text" value="$worldSize" style="width:110px" disabled /><button id="changeWorldSize" >Change</button></dd>
 							<dt>Layer Scale</dt><dd><input type="text" value="$layerScale" style="width:110px" disabled /><button id="changeLayerScale" >Change</button></dd>
+							<dt>World Offset</dt><dd><input type="text" value="$offsetX" style="width:50px" disabled/><input type="text" value="$offsetY" style="width:50px" disabled/><button id="changeWorldOffset" >Change</button></dd></dd>
 						</dl>
 						<dl>
 							<dt>Collide</dt>
@@ -717,6 +726,34 @@ class Layers2D extends hrt.prefab.Object3D {
 			}
 			ectx.rebuildProperties();
 		});
+
+		props.find("#changeWorldOffset").click(function(_) {
+			var input = hide.Ide.inst.ask("New world offset (x,y): ", offsetX + "," + offsetY);
+			if( input == null || input.length == 0 ) return;
+			var inputs = input.split(",");
+			if( inputs.length < 2) return;
+			var ox = Std.parseInt(inputs[0]), oy = Std.parseInt(inputs[1]);
+			if( Std.string(ox) != inputs[0] || Std.string(oy) != inputs[1] || (ox == offsetX && oy == offsetY) ) return;
+			var dox = Math.floor((ox - offsetX) / layerScale);
+			var doy = Math.floor((oy - offsetY) / layerScale);
+			var size = Math.floor(worldSize / layerScale);
+			var copySizeX = size - hxd.Math.iabs(dox);
+			var copySizeY = size - hxd.Math.iabs(doy);
+			offsetX = ox;
+			offsetY = oy;
+			for( key => layerTexture in layerTextures ) {
+				var newLayerTexture = hxd.Pixels.alloc(size, size, R8);
+				newLayerTexture.blit(
+					hxd.Math.imax(0, -dox), hxd.Math.imax(0, -doy), 
+					layerTexture, 
+					hxd.Math.imax(0, dox), hxd.Math.imax(0, doy),
+					copySizeX, copySizeY
+				);
+				layerTextures.set(key, newLayerTexture);
+			}
+			ectx.rebuildProperties();
+		});
+
 		var list = props.find("ul#layers");
 		ectx.properties.add(props,this, (pname) -> {
 			if ( pname == "collidePath" ) {