BabylonJS/Babylon.js · error · Error

FrameGraphMotionBlurTask "${this.name}": depthTexture is req

Error message

FrameGraphMotionBlurTask "${this.name}": depthTexture is required for screen-based motion blur

What it means

Thrown from the bindings callback of FrameGraphMotionBlurTask.record() when the post-process is in screen-based mode (isObjectBased === false) but depthTexture is undefined. Screen-based motion blur reconstructs motion from the depth buffer, so a depth texture must be bound.

Source

Thrown at packages/dev/core/src/FrameGraph/Tasks/PostProcesses/motionBlurTask.ts:52

        return "FrameGraphMotionBlurTask";
    }

    public override record(skipCreationOfDisabledPasses = false): FrameGraphRenderPass {
        if (this.sourceTexture === undefined) {
            throw new Error(`FrameGraphMotionBlurTask "${this.name}": sourceTexture is required`);
        }

        const pass = super.record(skipCreationOfDisabledPasses, undefined, (context) => {
            if (this.velocityTexture) {
                context.bindTextureHandle(this._postProcessDrawWrapper.effect!, "velocitySampler", this.velocityTexture);
            } else if (this.postProcess.isObjectBased) {
                throw new Error(`FrameGraphMotionBlurTask "${this.name}": velocityTexture is required for object-based motion blur`);
            }

            if (this.depthTexture) {
                context.bindTextureHandle(this._postProcessDrawWrapper.effect!, "depthSampler", this.depthTexture);
            } else if (!this.postProcess.isObjectBased) {
                throw new Error(`FrameGraphMotionBlurTask "${this.name}": depthTexture is required for screen-based motion blur`);
            }
        });

        pass.addDependencies(this.velocityTexture);
        pass.addDependencies(this.depthTexture);

        this.postProcess.textureWidth = this._sourceWidth;
        this.postProcess.textureHeight = this._sourceHeight;

        return pass;
    }
}

View on GitHub (pinned to 0592b347b8)

Solutions

1. Assign task.depthTexture to a depth texture handle (e.g. from a depth prepass task).
2. Alternatively switch the post-process to object-based mode if you meant to use velocity textures.
3. Ensure the depth-producing task is added to the frame graph before the motion blur task.
4. Confirm isObjectBased matches which texture (velocity vs depth) you actually wired.

Example fix

// before
const mb = new FrameGraphMotionBlurTask(frameGraph, "motionBlur");
mb.postProcess.screenBased = true;
mb.sourceTexture = colorTask.outputTexture;
// no depth wired

// after
const mb = new FrameGraphMotionBlurTask(frameGraph, "motionBlur");
mb.postProcess.screenBased = true;
mb.sourceTexture = colorTask.outputTexture;
mb.depthTexture = depthPrepassTask.outputTexture;

if (!mbTask.postProcess.isObjectBased && mbTask.depthTexture === undefined) {
  throw new Error("Screen-based motion blur requires depthTexture before build");
}

function depthWiredForMode(t: { postProcess: { isObjectBased: boolean }; depthTexture?: unknown }): boolean {
  return t.postProcess.isObjectBased || t.depthTexture !== undefined;
}

try {
  frameGraph.build();
} catch (e) {
  if (String(e?.message).includes("depthTexture is required for screen-based motion blur")) {
    console.error("Wire a depth texture or switch to object-based mode:", e.message);
  } else { throw e; }
}

When it happens

Trigger: Configuring the motion blur post-process for screen-based mode and building/rendering the graph without assigning task.depthTexture to a depth texture handle.

Common situations: Switching from object-based to screen-based mode and leaving the velocity texture wired instead of the depth texture; forgetting to add a depth-producing task (prepass/depth renderer) to the graph; samples copied across Babylon versions where defaults changed.

Related errors

• FrameGraphMotionBlurTask "${this.name}": sourceTexture is re
• FrameGraphMotionBlurTask "${this.name}": velocityTexture is
• FrameGraphDepthOfFieldBlurTask "${this.name}": sourceTexture
• FrameGraphBloomMergeTask "${this.name}": sourceTexture, circ
• FrameGraphDepthOfFieldTask: sourceTexture, depthTexture and

AI-assisted analysis of BabylonJS/Babylon.js@0592b347b8 (2026-08-30). Data as JSON: /api/errors/e3000bf9fb687d71. Report an issue: GitHub.