donner::gpu::RenderPassEncoder Class Reference

Encodes commands inside an active render pass. More...

#include "donner/gpu/CommandEncoder.h"

Public Member Functions
	RenderPassEncoder (const RenderPassEncoder &)=delete
RenderPassEncoder &	operator= (const RenderPassEncoder &)=delete
	RenderPassEncoder (RenderPassEncoder &&)=delete
RenderPassEncoder &	operator= (RenderPassEncoder &&)=delete
Status	setPipeline (const RenderPipeline &pipeline)
	Sets the active render pipeline.
Status	setBindGroup (uint32_t index, const BindGroup &bindGroup)
	Binds bindGroup at index.
Status	setVertexBuffer (uint32_t slot, const Buffer &buffer, uint64_t offsetBytes=0)
	Binds buffer as the vertex buffer for slot.
Status	setIndexBuffer (const Buffer &buffer, IndexFormat format, uint64_t offsetBytes=0)
	Binds buffer as the index buffer for subsequent drawIndexed calls.
Status	setScissorRect (uint32_t x, uint32_t y, uint32_t width, uint32_t height)
	Sets the scissor rectangle.
Status	setViewport (float x, float y, float width, float height, float minDepth, float maxDepth)
	Sets the viewport.
Status	draw (uint32_t vertexCount, uint32_t instanceCount=1, uint32_t firstVertex=0, uint32_t firstInstance=0)
	Records a draw.
Status	drawIndexed (uint32_t indexCount, uint32_t instanceCount=1, uint32_t firstIndex=0, int32_t baseVertex=0, uint32_t firstInstance=0)
	Records an indexed draw.
Status	end ()
	Ends the render pass. Further pass operations fail with GpuErrorType::InvalidState until a new pass begins.

Friends
class	CommandEncoder

Detailed Description

Encodes commands inside an active render pass.

Obtained from CommandEncoder::beginRenderPass; owned by the encoder and valid until the encoder is destroyed (operations after end fail with GpuErrorType::InvalidState).

Member Function Documentation

draw()

Status donner::gpu::RenderPassEncoder::draw	(	uint32_t	vertexCount,
		uint32_t	instanceCount = 1,
		uint32_t	firstVertex = 0,
		uint32_t	firstInstance = 0 )

Records a draw.

Fails closed unless a pipeline is set, every vertex buffer slot the pipeline declares is bound with enough bytes for the drawn range (checked arithmetic), and every bind group index the pipeline layout declares holds a bind group created against the same layout.

Parameters

vertexCount	Number of vertices.
instanceCount	Number of instances.
firstVertex	First vertex index.
firstInstance	First instance index.

drawIndexed()

Status donner::gpu::RenderPassEncoder::drawIndexed	(	uint32_t	indexCount,
		uint32_t	instanceCount = 1,
		uint32_t	firstIndex = 0,
		int32_t	baseVertex = 0,
		uint32_t	firstInstance = 0 )

Records an indexed draw.

For each of the indexCount indices starting at firstIndex in the bound index range, vertex-stepped attributes fetch element baseVertex + index value and instance-stepped attributes fetch element firstInstance + instance; the vertex stage sees the same sums as vertex_index and instance_index.

Fails closed unless a PrimitiveTopology::TriangleList pipeline is set (strips would need primitive-restart semantics the backends do not share, so they are refused with GpuErrorType::Unsupported), an index buffer is bound, the index range (firstIndex + indexCount) * indexWidth fits the bound range (checked 64-bit arithmetic), every declared vertex slot is bound, every instance-stepped slot covers firstInstance + instanceCount elements, and every bind group index the pipeline layout declares holds a group created against that layout.

Vertex-stepped ranges are NOT validated here: the element reached is baseVertex + index value, and index values live in GPU memory. Keeping every baseVertex + value inside the bound vertex buffers is the caller's responsibility; what an out-of-range vertex fetch returns, and whether the backend reports it, is backend-dependent and outside this contract.

A zero indexCount or instanceCount is recorded like draw records zero counts; the range checks still apply and backends issue no native draw for it.

Parameters

indexCount	Number of indices read.
instanceCount	Number of instances.
firstIndex	First index read, relative to the bound offset.
baseVertex	Signed value added to every index value before the vertex fetch.
firstInstance	First instance index.

setBindGroup()

Status donner::gpu::RenderPassEncoder::setBindGroup	(	uint32_t	index,
		const BindGroup &	bindGroup )

Binds bindGroup at index.

Compatibility with the active pipeline's layout is checked at draw time, so bind groups may be set before the pipeline.

Parameters

index	Bind group index; must be below kMaxBindGroups.
bindGroup	Bind group to bind; must be a live handle of the encoder's device.

setIndexBuffer()

Status donner::gpu::RenderPassEncoder::setIndexBuffer	(	const Buffer &	buffer,
		IndexFormat	format,
		uint64_t	offsetBytes = 0 )

Binds buffer as the index buffer for subsequent drawIndexed calls.

The bound range runs from offsetBytes to the end of the buffer; binding exactly at the end is allowed and yields an empty range. Rebinding replaces the format and range for later draws only, and the binding does not survive end.

Fails closed with GpuErrorType::Unsupported when the device cannot honor the full unsigned range of format (see Device::supportsFullIndexRange), so a 32-bit index that a driver would silently truncate is refused before any GPU work is recorded.

Parameters

buffer	Buffer to bind; needs BufferUsage::Index and must be a live handle of the encoder's device.
format	Width of each index.
offsetBytes	Byte offset of the first index; must be a multiple of the index width and within the buffer.

setPipeline()

Status donner::gpu::RenderPassEncoder::setPipeline

(

const RenderPipeline &

pipeline

)

Sets the active render pipeline.

Parameters

pipeline

Pipeline to bind; must be a live handle of the encoder's device.

setScissorRect()

Status donner::gpu::RenderPassEncoder::setScissorRect	(	uint32_t	x,
		uint32_t	y,
		uint32_t	width,
		uint32_t	height )

Sets the scissor rectangle.

The rectangle must fit inside the pass attachment extent.

Parameters

x	Left edge in pixels.
y	Top edge in pixels.
width	Width in pixels.
height	Height in pixels.

setVertexBuffer()

Status donner::gpu::RenderPassEncoder::setVertexBuffer	(	uint32_t	slot,
		const Buffer &	buffer,
		uint64_t	offsetBytes = 0 )

Binds buffer as the vertex buffer for slot.

Parameters

slot	Vertex buffer slot; must be below kMaxVertexBuffers.
buffer	Buffer to bind; needs BufferUsage::Vertex.
offsetBytes	Byte offset of the first element; must be within the buffer.

setViewport()

Status donner::gpu::RenderPassEncoder::setViewport	(	float	x,
		float	y,
		float	width,
		float	height,
		float	minDepth,
		float	maxDepth )

Sets the viewport.

All values must be finite, with positive extent and 0 <= minDepth <= maxDepth <= 1.

Parameters

x	Left edge in pixels.
y	Top edge in pixels.
width	Width in pixels.
height	Height in pixels.
minDepth	Minimum depth of the viewport range.
maxDepth	Maximum depth of the viewport range.

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The documentation for this class was generated from the following file:

• donner/gpu/CommandEncoder.h