name: render-textures

description: "Use this skill when using RenderTexture or DynamicTexture in Phaser 4. Covers drawing game objects to textures, dynamic texture creation, snapshot/screenshot, stamps, and off-screen rendering. Triggers on: RenderTexture, DynamicTexture, snapshot, draw to texture, stamp."

Render Textures and Dynamic Textures

Drawing game objects to off-screen textures in Phaser 4 -- RenderTexture game object, DynamicTexture for shared textures, the Stamp helper, command-buffer rendering, snapshots, procedural generation, and minimap patterns.

Key source paths: src/gameobjects/rendertexture/, src/textures/DynamicTexture.js, src/gameobjects/stamp/, src/textures/typedefs/StampConfig.js, src/textures/typedefs/CaptureConfig.js

Related skills: ../sprites-and-images/SKILL.md, ../loading-assets/SKILL.md, ../cameras/SKILL.md

Quick Start

// In a Scene's create() method:

// 1. RenderTexture -- a visible game object with its own DynamicTexture
const rt = this.add.renderTexture(400, 300, 256, 256);
rt.draw('player', 128, 128);          // draw a texture by key at center
rt.fill(0x222244, 0.5);               // semi-transparent fill
rt.render();                           // flush the command buffer

// 2. DynamicTexture -- a shared texture in the Texture Manager
const dt = this.textures.addDynamicTexture('composite', 512, 512);
dt.stamp('coin', null, 64, 64, { scale: 2, angle: 45 });
dt.render();
this.add.image(400, 300, 'composite'); // any game object can use it

// 3. Stamp game object -- lightweight Image that ignores camera scroll
const hud = this.add.stamp(10, 10, 'heart');

Core Concepts

RenderTexture vs DynamicTexture

Phaser 4 splits texture-drawing into two layers:

When to use which:

• Use RenderTexture when you need a single visible surface you draw onto (paint canvas, trail effect, composite sprite).
• Use DynamicTexture when many game objects share the same generated texture, or you need a texture for masks/shaders, or you need cross-scene access.

RenderTexture is a thin proxy. Methods like draw(), stamp(), fill(), clear(), erase(), snapshot() all delegate to its underlying this.texture (a DynamicTexture).

Origin note: RenderTexture extends Image, so its origin defaults to (0.5, 0.5). If you want top-left positioning (common for full-screen or minimap RTs), call rt.setOrigin(0, 0).

The Command Buffer (v4 Architecture)

In Phaser 4, drawing calls (draw, stamp, fill, clear, erase, repeat, capture) do not execute immediately. They push commands into a commandBuffer array. You must call .render() to flush and execute the buffer.

rt.clear();
rt.fill(0x000000);
rt.draw(sprite, 128, 128);
rt.render();  // REQUIRED -- nothing appears without this

For RenderTexture game objects, the renderMode property controls automatic rendering:

rt.setRenderMode('all');       // auto-render + display every frame
rt.setRenderMode('all', true); // same, plus preserve the command buffer

Preserve Mode

By default the command buffer clears after render(). Call preserve(true) to keep commands between renders, so the same drawing replays each frame:

rt.preserve(true);
rt.clear();
rt.draw(sprite);
// On every subsequent render(), clear + draw will repeat

Stamp Game Object

Stamp (this.add.stamp(x, y, texture, frame)) is a lightweight Image subclass that ignores camera scroll and transform during rendering. It is used internally by DynamicTexture for drawing operations and is also useful for HUD elements. It extends Image with custom render nodes (DefaultStampNodes).

The stamp() Method vs the Stamp Game Object

These are different things:

• **rt.stamp(key, frame, x, y, config)** -- a method on RenderTexture/DynamicTexture that draws a texture frame to the surface with transform options (alpha, tint, angle, scale, origin, blendMode).
• **this.add.stamp(x, y, texture, frame)** -- a factory that creates