# Stuck. Attempt at creating an Infinite Treadmill Terrain with Away3D 5.0.9 (Code included)
**URL:** https://community.haxe.org/t/stuck-attempt-at-creating-an-infinite-treadmill-terrain-with-away3d-5-0-9-code-included/4772
**Category:** Haxe
**Created:** [February 15, 2026, 12:30am UTC](https://community.haxe.org/t/stuck-attempt-at-creating-an-infinite-treadmill-terrain-with-away3d-5-0-9-code-included/4772 "2026-02-15T00:30:42Z")
**Posts on this page:** 3
**Page:** 1
### Author:  [@jul](https://community.haxe.org/u/jul)
#### Post date: [February 15, 2026, 12:30am UTC](https://community.haxe.org/t/stuck-attempt-at-creating-an-infinite-treadmill-terrain-with-away3d-5-0-9-code-included/4772/1 "2026-02-15T00:30:42Z")
So far, this is the best result I have been able to achieve…
(Haxe 4.3.6, Away3D 5.0.9, OpenFl 9.5.0, Lime 8.3.0, Hxcpp 4.3.2)
It’s supposed to be an heightmap based terrain, with volumes of course, but it’s all flat. Of course. But it scrolls and displays the texture. I can’t go any further. If someone wants to try and figure out how to achieve the final step, here’s the code.
Project.xml
```xml
```
Main.hx
```haxe
package;
import away3d.containers.View3D;
import away3d.lights.DirectionalLight;
import away3d.materials.lightpickers.StaticLightPicker;
import away3d.textures.BitmapTexture;
import openfl.display.Sprite;
import openfl.events.Event;
import openfl.utils.Assets;
import openfl.display.BitmapData;
import openfl.geom.Vector3D;
class Main extends Sprite {
private var _view:View3D;
private var _terrain:TerrainManager;
public function new() {
super();
if (Assets.exists("assets/heightMap.jpg")) {
Assets.loadBitmapData("assets/heightMap.jpg").onComplete(init);
} else {
// Fallback: Create a procedural green grid if file is missing
var bmd = new BitmapData(512, 512, false, 0);
bmd.perlinNoise(72, 72, 4, 12, true, true, 7, true);
init(bmd);
}
}
private function init(textureData:BitmapData):Void {
_view = new View3D();
_view.backgroundColor = 0x87CEEB;
addChild(_view);
_view.camera.lens.far = 250000;
_view.camera.y = 6000;
var light = new DirectionalLight(-0.5, -1, 0.5);
light.ambient = 0.4;
_view.scene.addChild(light);
var lightPicker = new StaticLightPicker([light]);
var texture = new BitmapTexture(textureData);
_terrain = new TerrainManager(texture, lightPicker);
_view.scene.addChild(_terrain.mesh);
addEventListener(Event.ENTER_FRAME, onEnterFrame);
}
private function onEnterFrame(e:Event):Void {
if (_view != null && _terrain != null) {
// Continuous movement
_view.camera.z += 100;
// Update terrain using camera position
_terrain.update(_view.camera.position);
_view.render();
}
}
}
```
TerrainManager.hx
```haxe
package;
import away3d.entities.Mesh;
import away3d.materials.TextureMaterial;
import away3d.materials.lightpickers.StaticLightPicker;
import away3d.primitives.PlaneGeometry;
import away3d.textures.BitmapTexture;
import away3d.bounds.BoundingSphere;
import openfl.geom.Vector3D;
class TerrainManager {
public var mesh:Mesh;
private var _method:VertexDisplacementMethod;
private var _gridSize:Float = 150000;
public function new(texture:BitmapTexture, lightPicker:StaticLightPicker) {
// High density (200 segments) makes mountains look like your image
var geometry = new PlaneGeometry(_gridSize, _gridSize, 200, 200);
_method = new VertexDisplacementMethod(50000);
var material = new TextureMaterial(texture);
material.lightPicker = lightPicker;
material.repeat = true;
material.ambient = 0.5;
material.addMethod(_method);
mesh = new Mesh(geometry, material);
mesh.bounds = new BoundingSphere();
// Massively tall bounding box to never cull the volume
mesh.bounds.fromExtremes(-200000, -100000, -200000, 200000, 100000, 200000);
}
public function update(cameraPos:Vector3D):Void {
// Fix the mesh to the camera center. NO SNAPPING = NO JITTER.
mesh.x = cameraPos.x;
mesh.z = cameraPos.z;
// Tell the shader where the camera is so it can offset the math
_method.setCameraPosition(cameraPos.x, cameraPos.z);
}
}
```
VertexDisplacementMethod.hx
```haxe
package;
import away3d.materials.methods.EffectMethodBase;
import away3d.materials.methods.MethodVO;
import away3d.materials.compilation.ShaderRegisterCache;
import away3d.materials.compilation.ShaderRegisterElement;
import away3d.core.managers.Stage3DProxy;
import openfl.Vector;
class VertexDisplacementMethod extends EffectMethodBase {
private var _camX:Float = 0;
private var _camZ:Float = 0;
private var _amplitude:Float;
public function new(amplitude:Float = 40000) {
super();
_amplitude = amplitude;
}
public function setCameraPosition(x:Float, z:Float):Void {
_camX = x;
_camZ = z;
}
override public function initVO(vo:MethodVO):Void {
vo.needsUV = true;
}
override public function activate(vo:MethodVO, stage3DProxy:Stage3DProxy):Void {
var vIndex:Int = vo.vertexConstantsIndex;
if (vIndex != -1) {
var vData:Vector = vo.vertexData;
// vcN: [CameraX, CameraZ, Amplitude, TextureScale]
vData[vIndex] = _camX;
vData[vIndex + 1] = _camZ;
vData[vIndex + 2] = _amplitude;
vData[vIndex + 3] = 0.000008; // Huge scale for large terrain
// vcN+1: [Freq1, Freq2, Freq3, DetailPersistence]
vData[vIndex + 4] = 0.0001;
vData[vIndex + 5] = 0.0003;
vData[vIndex + 6] = 0.0009;
vData[vIndex + 7] = 0.45;
}
}
override public function getVertexCode(vo:MethodVO, regCache:ShaderRegisterCache):String {
var dataReg:ShaderRegisterElement = regCache.getFreeVertexConstant();
var mathReg:ShaderRegisterElement = regCache.getFreeVertexConstant();
vo.vertexConstantsIndex = dataReg.index * 4;
var world:ShaderRegisterElement = regCache.getFreeVertexVectorTemp();
var hReg:ShaderRegisterElement = regCache.getFreeVertexVectorTemp();
var tReg:ShaderRegisterElement = regCache.getFreeVertexVectorTemp();
var code:String = "";
// 1. CALCULATE WORLD POS: Camera + Local
code += "add " + world + ".x, vt0.x, " + dataReg + ".x \n";
code += "add " + world + ".z, vt0.z, " + dataReg + ".y \n";
// 2. PROJECT UVs: Makes the texture stay pinned to the world
code += "mul v0.xy, " + world + ".xz, " + dataReg + ".w \n";
// 3. FRACTAL MOUNTAINS (Ridged Noise Math)
// Octave 1: Large Hills
code += "mul " + tReg + ".xz, " + world + ".xz, " + mathReg + ".x \n";
code += "sin " + hReg + ".x, " + tReg + ".x \n";
code += "cos " + hReg + ".y, " + tReg + ".z \n";
code += "mul " + hReg + ".z, " + hReg + ".x, " + hReg + ".y \n";
code += "abs " + hReg + ".z, " + hReg + ".z \n"; // Sharp peaks
// Octave 2: Ridges
code += "mul " + tReg + ".xz, " + world + ".xz, " + mathReg + ".y \n";
code += "sin " + tReg + ".x, " + tReg + ".x \n";
code += "cos " + tReg + ".y, " + tReg + ".z \n";
code += "mul " + tReg + ".x, " + tReg + ".x, " + tReg + ".y \n";
code += "abs " + tReg + ".x, " + tReg + ".x \n";
code += "mul " + tReg + ".x, " + tReg + ".x, " + mathReg + ".w \n"; // Apply persistence
code += "add " + hReg + ".z, " + hReg + ".z, " + tReg + ".x \n";
// 4. APPLY DISPLACEMENT
code += "mul " + hReg + ".z, " + hReg + ".z, " + dataReg + ".z \n";
code += "add vt0.y, vt0.y, " + hReg + ".z \n";
return code;
}
override public function getFragmentCode(vo:MethodVO, regCache:ShaderRegisterCache, targetReg:ShaderRegisterElement):String {
return "";
}
}
```
Good luck.
---
### Author:  [@kevin-kmetz](https://community.haxe.org/u/kevin-kmetz)
#### Post date: [February 15, 2026, 1:24am UTC](https://community.haxe.org/t/stuck-attempt-at-creating-an-infinite-treadmill-terrain-with-away3d-5-0-9-code-included/4772/2 "2026-02-15T01:24:07Z")
This open pull request ( [Allow effect methods to modify vertex position. by player-03 · Pull Request #67 · openfl/away3d · GitHub](https://github.com/openfl/away3d/pull/67) ) from @player_03 seems to suggest that effect methods cannot alter vertices.
This is way above my head though, so I could be wrong. Curious to hear what others think.
---
### Author:  [@player\_03](https://community.haxe.org/u/player_03)
#### Post date: [February 19, 2026, 7:40pm UTC](https://community.haxe.org/t/stuck-attempt-at-creating-an-infinite-treadmill-terrain-with-away3d-5-0-9-code-included/4772/3 "2026-02-19T19:40:42Z")
Yes, as it stands, effect methods can’t alter vertex positions. Here’s the order of operations:
1. [Designate a temporary value to be `localPosition`](https://github.com/openfl/away3d/blob/5a0b89f1a83d57b74d6cf4fa782d74c93434b510/away3d/materials/compilation/ShaderCompiler.hx#L313). (Aside: I’d suggest using `sharedRegisters.localPosition` instead of hard-coding `vt0`, just in case it ever changes. It seems unlikely given that Away3D hard-codes it in places too, but better safe than sorry.)
2. [Project `localPosition` and assign it to `op`](https://github.com/openfl/away3d/blob/5a0b89f1a83d57b74d6cf4fa782d74c93434b510/away3d/materials/compilation/ShaderCompiler.hx#L326). `vt0` is now only for reference, since `op` can (I think) only be set once.
3. [Run effect methods](https://github.com/openfl/away3d/blob/5a0b89f1a83d57b74d6cf4fa782d74c93434b510/away3d/materials/compilation/ShaderCompiler.hx#L327). This is where your code goes.
Give my PR a try, and if it helps, please leave a comment!