From 6e21320f0963a3fe05909be066ec9534daba9d87 Mon Sep 17 00:00:00 2001
From: Coopus <120044030+CoopusDev@users.noreply.github.com>
Date: Sat, 23 Mar 2024 20:06:17 +0800
Subject: [PATCH] fix z-fighting in an example

---
 site/pages/gallery/Axes.astro   |  2 --
 src/mobjects/Axes.js            | 11 +++++++++--
 src/mobjects/FunctionGraph2D.js |  7 ++++---
 types.d.ts                      | 10 ++++++++--
 4 files changed, 21 insertions(+), 9 deletions(-)

diff --git a/site/pages/gallery/Axes.astro b/site/pages/gallery/Axes.astro
index 5e9da920..6438d346 100644
--- a/site/pages/gallery/Axes.astro
+++ b/site/pages/gallery/Axes.astro
@@ -12,8 +12,6 @@ import Example from "../../layouts/Example.astro";
         const axes = new mp.Axes({
             xRange: [-10, 10, 1], // You can set the length of every axis like this
         });
-        axes.material = new mp.MobjectMaterial();
-        axes.material.depthTest = false;
 
         // Draw function figures
         const figure0 = axes.drawFunction2D((x) => x);
diff --git a/src/mobjects/Axes.js b/src/mobjects/Axes.js
index 5392c4b6..39ea9c7a 100644
--- a/src/mobjects/Axes.js
+++ b/src/mobjects/Axes.js
@@ -25,6 +25,8 @@ export default class Axes extends Graph2D {
         this.yRange = yRange;
         this.zRange = zRange;
 
+        this.graphs = [];
+
         this.addChild(this.xAxis);
         this.addChild(this.yAxis);
         this.addChild(this.zAxis);
@@ -44,12 +46,17 @@ export default class Axes extends Graph2D {
         }
     }
 
-    drawFunction2D(func, step = 0.1) {
+    drawFunction2D(func, { step = 0.1, autoStack = true } = {}) {
         const range = this.xRange;
         range[2] = step;
-        const graph = new FunctionGraph2D(func, { xRange: range });
+        const last = this.graphs[this.graphs.length - 1];
+        const z = autoStack && last ? last.z + 0.001 : 0.01;
+
+        const graph = new FunctionGraph2D(func, { xRange: range, z: z });
         graph.update();
+
         this.addChild(graph);
+        this.graphs.push(graph);
         return graph;
     }
 
diff --git a/src/mobjects/FunctionGraph2D.js b/src/mobjects/FunctionGraph2D.js
index 9a48ad6b..a739a573 100644
--- a/src/mobjects/FunctionGraph2D.js
+++ b/src/mobjects/FunctionGraph2D.js
@@ -1,10 +1,11 @@
 import Graph2D from "./Graph2D.js";
 
 export default class FunctionGraph2D extends Graph2D {
-    constructor(func = (x) => x, { xRange = [-8, 8, 0.1] } = {}) {
+    constructor(func = (x) => x, { xRange = [-8, 8, 0.1], z = 0 } = {}) {
         super();
         this.xRange = xRange;
         this.func = func;
+        this.z = z;
     }
 
     update() {
@@ -14,9 +15,9 @@ export default class FunctionGraph2D extends Graph2D {
         const func = this.func;
 
         this.clear();
-        this.move([from, func(from), 0]);
+        this.move([from, func(from), this.z]);
         for (let i = from + step; i <= to; i += step) {
-            this.line([i, func(i), 0]);
+            this.line([i, func(i), this.z]);
         }
         this.stroke();
         return this;
diff --git a/types.d.ts b/types.d.ts
index fc6f0367..f6a7d688 100644
--- a/types.d.ts
+++ b/types.d.ts
@@ -1445,11 +1445,13 @@ declare module "mobjects/Axis" {
 }
 declare module "mobjects/FunctionGraph2D" {
     export default class FunctionGraph2D extends Graph2D {
-        constructor(func?: (x: any) => any, { xRange }?: {
+        constructor(func?: (x: any) => any, { xRange, z }?: {
             xRange?: number[];
+            z?: number;
         });
         xRange: number[];
         func: (x: any) => any;
+        z: number;
         update(): this;
         redraw(): this;
     }
@@ -1471,8 +1473,12 @@ declare module "mobjects/Axes" {
         xRange: number[];
         yRange: number[];
         zRange: number[];
+        graphs: any[];
         addTip(): void;
-        drawFunction2D(func: any, step?: number): FunctionGraph2D;
+        drawFunction2D(func: any, { step, autoStack }?: {
+            step?: number;
+            autoStack?: boolean;
+        }): FunctionGraph2D;
         set tickLength(val: number);
         get tickLength(): number;
     }