## C Specification

The VkDrawIndexedIndirectCommand structure is defined as:

typedef struct VkDrawIndexedIndirectCommand {
uint32_t    indexCount;
uint32_t    instanceCount;
uint32_t    firstIndex;
int32_t     vertexOffset;
uint32_t    firstInstance;
} VkDrawIndexedIndirectCommand;

## Members

• indexCount is the number of vertices to draw.

• instanceCount is the number of instances to draw.

• firstIndex is the base index within the index buffer.

• vertexOffset is the value added to the vertex index before indexing into the vertex buffer.

• firstInstance is the instance ID of the first instance to draw.

## Description

The members of VkDrawIndexedIndirectCommand have the same meaning as the similarly named parameters of vkCmdDrawIndexed.

Valid Usage
• For a given vertex buffer binding, any attribute data fetched must be entirely contained within the corresponding vertex buffer binding, as described in https://www.khronos.org/registry/vulkan/specs/1.1-extensions/html/vkspec.html#fxvertex-input

• (indexSize * (firstIndex + indexCount) + offset) must be less than or equal to the size of the bound index buffer, with indexSize being based on the type specified by indexType, where the index buffer, indexType, and offset are specified via vkCmdBindIndexBuffer

• If the drawIndirectFirstInstance feature is not enabled, firstInstance must be 0