From c8987c9515bfe03258acbcaf11e6d50297c2ba6b Mon Sep 17 00:00:00 2001
From: Marcus Cazzola Helms <marcus.cazzola-helms@hacksawstudios.com>
Date: Tue, 28 Oct 2025 16:54:58 +0100
Subject: [PATCH] add anti aliasing option

---
 h2d/RenderContext.hx       |  3 +++
 h3d/scene/RenderContext.hx |  6 ++++++
 h3d/shader/Texture.hx      | 20 ++++++++++++++++++++
 3 files changed, 29 insertions(+)

diff --git a/h2d/RenderContext.hx b/h2d/RenderContext.hx
index 86a1413bef..a494fbc48c 100644
--- a/h2d/RenderContext.hx
+++ b/h2d/RenderContext.hx
@@ -151,6 +151,9 @@ class RenderContext extends h3d.impl.RenderContext {
 		cameraStackIndex = 0;
 		filterStack = [];
 		filterStackIndex = 0;
+		#if anti_aliasing
+		globals.set("global.antiAliasing", 0);
+		#end
 	}
 
 	override function dispose() {
diff --git a/h3d/scene/RenderContext.hx b/h3d/scene/RenderContext.hx
index 349eba2ae6..80ba969e20 100644
--- a/h3d/scene/RenderContext.hx
+++ b/h3d/scene/RenderContext.hx
@@ -46,6 +46,9 @@ class RenderContext extends h3d.impl.RenderContext {
 	@global("global.modelViewInverse") var globalModelViewInverse : h3d.Matrix;
 	@global("global.previousModelView") var globalPreviousModelView : h3d.Matrix;
 	@global("global.frame") var globalFrame : Int;
+	#if anti_aliasing
+	@global("global.antiAliasing") var globalAntiAliasing : Int;
+	#end
 
 	var allocPool : h3d.pass.PassObject;
 	var allocFirst : h3d.pass.PassObject;
@@ -67,6 +70,9 @@ class RenderContext extends h3d.impl.RenderContext {
 		cachedShaderList = [];
 		cachedPassObjects = [];
 		initGlobals();
+		#if anti_aliasing
+		globalAntiAliasing = 0;
+		#end
 	}
 
 	public function setCamera( cam : h3d.Camera ) {
diff --git a/h3d/shader/Texture.hx b/h3d/shader/Texture.hx
index 1b431cd926..b7d04f3c25 100644
--- a/h3d/shader/Texture.hx
+++ b/h3d/shader/Texture.hx
@@ -6,6 +6,12 @@ class Texture extends hxsl.Shader {
 		@input var input : {
 			var uv : Vec2;
 		};
+		
+		#if anti_aliasing
+		@global var global: { 
+            var antiAliasing: Int; 
+        };
+		#end
 
 		@const var additive : Bool;
 		@const var killAlpha : Bool;
@@ -22,7 +28,21 @@ class Texture extends hxsl.Shader {
 		}
 
 		function fragment() {
+			#if anti_aliasing
+			var c = if (global.antiAliasing == 1) {
+				var dx = dFdx(input.uv);
+				var dy = dFdy(input.uv);
+				var c0 = texture.get(input.uv + 0.25 * dx + 0.25 * dy);
+				var c1 = texture.get(input.uv + 0.25 * dx - 0.25 * dy);
+				var c2 = texture.get(input.uv - 0.25 * dx + 0.25 * dy);
+				var c3 = texture.get(input.uv - 0.25 * dx - 0.25 * dy);
+				(c0 + c1 + c2 + c3) * 0.25;
+			} else {
+				texture.get(calculatedUV);
+			}
+			#else
 			var c = texture.get(calculatedUV);
+			#end
 			if( killAlpha && c.a - killAlphaThreshold < 0 ) discard;
 			if( additive )
 				pixelColor += c;