GpuBuffer

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Import: import system.gpu;

This reference lists the public declarations for this part of the library. See Reading API signatures for parameter and result notation. Shader-only declarations can be used only inside shader entry points and helpers reached from them; using them elsewhere is a compile error.

GpuBuffer

An array of T in GPU memory. Create one with GpuDevice.buffer_from, buffer_alloc, vertex_buffer_from or index_buffer_from, and pass it to shaders. Inside a shader, buffer[i] reads and writes element i; a parameter marked @readonly can only be read. On the CPU, write uploads new contents and read downloads them after the GPU finished. T must be a type without references, such as float, int, GpuVec4 or a struct of them.

public class GpuBuffer<T: unmanaged>

length

The number of elements.

public get length(): int

write

Replaces the whole contents with data, which must have exactly length elements.

public fun write(data: T[]): Result<Unit, GpuError>

write_at

Replaces the elements starting at offset with data. The range must lie inside the buffer. On GpuBackend.WebGpu it must also start at a multiple of 4 bytes and end at one or at the end of the buffer, which matters for float16 and byte elements.

public fun write_at(offset: int, data: T[]): Result<Unit, GpuError>

read

Downloads every element. It waits for submitted GPU work that writes the buffer.

public async fun read(): Result<T[], GpuError>

destroy

Releases the GPU memory as soon as submitted work that uses it has finished. Later uses return GpuError.InvalidResource. Releasing the last reference does the same.

public fun destroy(): void

this

Reads element index inside a shader. Indexes outside the buffer read zero on most backends; never rely on it.

public extern fun this[index: int]: T

this

Writes element index inside a shader. Not allowed on @readonly parameters. Writes outside the buffer are dropped.

public extern fun this[index: int] = value: T