GPURenderPassEncoder: draw() method
Experimental: This is an experimental technology
Check the Browser compatibility table carefully before using this in production.
The draw()
method of the
GPURenderPassEncoder
interface draws primitives based on the vertex buffers provided by setVertexBuffer()
.
Syntax
js
draw(vertexCount)
draw(vertexCount, instanceCount)
draw(vertexCount, instanceCount, firstVertex)
draw(vertexCount, instanceCount, firstVertex, firstInstance)
Parameters
vertexCount
-
A number defining the number of vertices to draw.
instanceCount
Optional-
A number defining the number of instances to draw. If omitted,
instanceCount
defaults to 1. firstVertex
Optional-
A number defining the offset into the vertex buffers, in vertices, to begin drawing from. If omitted,
firstVertex
defaults to 0. firstInstance
Optional-
A number defining the first instance to draw. If omitted,
firstInstance
defaults to 0.
Return value
None (Undefined
).
Examples
In our basic render demo, several commands are recorded via a GPUCommandEncoder
. Most of these commands originate from the GPURenderPassEncoder
created via GPUCommandEncoder.beginRenderPass()
. draw()
is used to specify that three vertices should be drawn to create our triangle.
js
// ...
const renderPipeline = device.createRenderPipeline(pipelineDescriptor);
// Create GPUCommandEncoder to issue commands to the GPU
// Note: render pass descriptor, command encoder, etc. are destroyed after use, fresh one needed for each frame.
const commandEncoder = device.createCommandEncoder();
// Create GPURenderPassDescriptor to tell WebGPU which texture to draw into, then initiate render pass
const renderPassDescriptor = {
colorAttachments: [
{
clearValue: clearColor,
loadOp: "clear",
storeOp: "store",
view: context.getCurrentTexture().createView(),
},
],
};
const passEncoder = commandEncoder.beginRenderPass(renderPassDescriptor);
// Draw the triangle
passEncoder.setPipeline(renderPipeline);
passEncoder.setVertexBuffer(0, vertexBuffer);
passEncoder.draw(3);
// End the render pass
passEncoder.end();
// End frame by passing array of command buffers to command queue for execution
device.queue.submit([commandEncoder.finish()]);
// ...
Specifications
Specification |
---|
WebGPU # dom-gpurendercommandsmixin-draw |
Browser compatibility
BCD tables only load in the browser
See also
- The WebGPU API