Struct Draw

pub struct Draw<'a> { /* private fields */ }

Recording interface for drawing commands.

This structure provides a strongly-typed set of methods which allow rasterization shader code to be executed. An instance of Draw is provided to the closure parameter of PipelinePassRef::record_subpass which may be accessed by binding a GraphicPipeline to a render pass.

Examples

Basic usage:

my_graph.begin_pass("my draw pass")
        .bind_pipeline(&my_graphic_pipeline)
        .store_color(0, swapchain_image)
        .record_subpass(move |subpass, bindings| {
            // During this closure we have access to the draw methods!
        });

Implementations

impl Draw<'_>

pub fn bind_index_buffer( &self, buffer: impl Into<AnyBufferNode>, index_ty: IndexType, ) -> &Self

Bind an index buffer to the current pass.

Examples

Basic usage:

my_graph.begin_pass("my indexed geometry draw pass")
        .bind_pipeline(&my_graphic_pipeline)
        .store_color(0, swapchain_image)
        .read_node(my_idx_buf)
        .read_node(my_vtx_buf)
        .record_subpass(move |subpass, bindings| {
            subpass.bind_index_buffer(my_idx_buf, vk::IndexType::UINT16)
                   .bind_vertex_buffer(my_vtx_buf)
                   .draw_indexed(42, 1, 0, 0, 0);
        });

pub fn bind_index_buffer_offset( &self, buffer: impl Into<AnyBufferNode>, index_ty: IndexType, offset: DeviceSize, ) -> &Self

Bind an index buffer to the current pass.

Behaves similarly to bind_index_buffer except that offset is the starting offset in bytes within buffer used in index buffer address calculations.

pub fn bind_vertex_buffer(&self, buffer: impl Into<AnyBufferNode>) -> &Self

Bind a vertex buffer to the current pass.

Examples

Basic usage:

my_graph.begin_pass("my unindexed geometry draw pass")
        .bind_pipeline(&my_graphic_pipeline)
        .store_color(0, swapchain_image)
        .read_node(my_vtx_buf)
        .record_subpass(move |subpass, bindings| {
            subpass.bind_vertex_buffer(my_vtx_buf)
                   .draw(42, 1, 0, 0);
        });

pub fn bind_vertex_buffer_offset( &self, buffer: impl Into<AnyBufferNode>, offset: DeviceSize, ) -> &Self

Bind a vertex buffer to the current pass.

Behaves similarly to bind_vertex_buffer except the vertex input binding is updated to start at offset from the start of buffer.

pub fn bind_vertex_buffers<B>( &self, first_binding: u32, buffer_offsets: impl IntoIterator<Item = (B, DeviceSize)>, ) -> &Self

where B: Into<AnyBufferNode>,

Binds multiple vertex buffers to the current pass, starting at the given first_binding.

Each vertex input binding in buffers specifies an offset from the start of the corresponding buffer.

The vertex input attributes that use each of these bindings will use these updated addresses in their address calculations for subsequent drawing commands.

pub fn draw( &self, vertex_count: u32, instance_count: u32, first_vertex: u32, first_instance: u32, ) -> &Self

Draw unindexed primitives.

When the command is executed, primitives are assembled using the current primitive topology and vertex_count consecutive vertex indices with the first vertex_index value equal to first_vertex. The primitives are drawn instance_count times with instance_index starting with first_instance and increasing sequentially for each instance.

pub fn draw_indexed( &self, index_count: u32, instance_count: u32, first_index: u32, vertex_offset: i32, first_instance: u32, ) -> &Self

Draw indexed primitives.

When the command is executed, primitives are assembled using the current primitive topology and index_count vertices whose indices are retrieved from the index buffer. The index buffer is treated as an array of tightly packed unsigned integers of size defined by the index_ty parameter with which the buffer was bound.

pub fn draw_indexed_indirect( &self, buffer: impl Into<AnyBufferNode>, offset: DeviceSize, draw_count: u32, stride: u32, ) -> &Self

Draw primitives with indirect parameters and indexed vertices.

draw_indexed_indirect behaves similarly to draw_indexed except that the parameters are read by the device from buffer during execution. draw_count draws are executed by the command, with parameters taken from buffer starting at offset and increasing by stride bytes for each successive draw. The parameters of each draw are encoded in an array of vk::DrawIndexedIndirectCommand structures.

If draw_count is less than or equal to one, stride is ignored.

Examples

Basic usage:

const CMD_SIZE: usize = size_of::<vk::DrawIndexedIndirectCommand>();

let cmd = vk::DrawIndexedIndirectCommand {
    index_count: 3,
    instance_count: 1,
    first_index: 0,
    vertex_offset: 0,
    first_instance: 0,
};
let cmd_data = unsafe {
    std::slice::from_raw_parts(&cmd as *const _ as *const _, CMD_SIZE)
};

let buf_flags = vk::BufferUsageFlags::STORAGE_BUFFER;
let buf = Buffer::create_from_slice(&device, buf_flags, cmd_data)?;
let buf_node = my_graph.bind_node(buf);

my_graph.begin_pass("draw a single triangle")
        .bind_pipeline(&my_graphic_pipeline)
        .store_color(0, swapchain_image)
        .read_node(my_idx_buf)
        .read_node(my_vtx_buf)
        .read_node(buf_node)
        .record_subpass(move |subpass, bindings| {
            subpass.bind_index_buffer(my_idx_buf, vk::IndexType::UINT16)
                   .bind_vertex_buffer(my_vtx_buf)
                   .draw_indexed_indirect(buf_node, 0, 1, 0);
        });

pub fn draw_indexed_indirect_count( &self, buffer: impl Into<AnyBufferNode>, offset: DeviceSize, count_buf: impl Into<AnyBufferNode>, count_buf_offset: DeviceSize, max_draw_count: u32, stride: u32, ) -> &Self

Draw primitives with indirect parameters, indexed vertices, and draw count.

draw_indexed_indirect_count behaves similarly to draw_indexed_indirect except that the draw count is read by the device from buffer during execution. The command will read an unsigned 32-bit integer from count_buf located at count_buf_offset and use this as the draw count.

max_draw_count specifies the maximum number of draws that will be executed. The actual number of executed draw calls is the minimum of the count specified in count_buf and max_draw_count.

stride is the byte stride between successive sets of draw parameters.

pub fn draw_indirect( &self, buffer: impl Into<AnyBufferNode>, offset: DeviceSize, draw_count: u32, stride: u32, ) -> &Self

Draw primitives with indirect parameters and unindexed vertices.

Behaves otherwise similar to Draw::draw_indexed_indirect.

pub fn draw_indirect_count( &self, buffer: impl Into<AnyBufferNode>, offset: DeviceSize, count_buf: impl Into<AnyBufferNode>, count_buf_offset: DeviceSize, max_draw_count: u32, stride: u32, ) -> &Self

Draw primitives with indirect parameters, unindexed vertices, and draw count.

Behaves otherwise similar to Draw::draw_indexed_indirect_count.

pub fn push_constants(&self, data: &[u8]) -> &Self

Updates push constants.

Push constants represent a high speed path to modify constant data in pipelines that is expected to outperform memory-backed resource updates.

Push constant values can be updated incrementally, causing shader stages to read the new data for push constants modified by this command, while still reading the previous data for push constants not modified by this command.

Device limitations

See device.physical_device.props.limits.max_push_constants_size for the limits of the current device. You may also check gpuinfo.org for a listing of reported limits on other devices.

Examples

Basic usage:

#version 450

layout(push_constant) uniform PushConstants {
    layout(offset = 0) uint the_answer;
} push_constants;

void main()
{
    // TODO: Add code!
}

my_graph.begin_pass("draw a quad")
        .bind_pipeline(&my_graphic_pipeline)
        .store_color(0, swapchain_image)
        .record_subpass(move |subpass, bindings| {
            subpass.push_constants(&[42])
                   .draw(6, 1, 0, 0);
        });

pub fn push_constants_offset(&self, offset: u32, data: &[u8]) -> &Self

Updates push constants starting at the given offset.

Behaves similary to Draw::push_constants except that offset describes the position at which data updates the push constants of the currently bound pipeline. This may be used to update a subset or single field of previously set push constant data.

Device limitations

See device.physical_device.props.limits.max_push_constants_size for the limits of the current device. You may also check gpuinfo.org for a listing of reported limits on other devices.

Examples

Basic usage:

#version 450

layout(push_constant) uniform PushConstants {
    layout(offset = 0) uint some_val1;
    layout(offset = 4) uint some_val2;
} push_constants;

void main()
{
    // TODO: Add code!
}

my_graph.begin_pass("draw a quad")
        .bind_pipeline(&my_graphic_pipeline)
        .store_color(0, swapchain_image)
        .record_subpass(move |subpass, bindings| {
            subpass.push_constants(&[0x00, 0x00])
                   .draw(6, 1, 0, 0)
                   .push_constants_offset(4, &[0xff])
                   .draw(6, 1, 0, 0);
        });

pub fn set_scissor(&self, x: i32, y: i32, width: u32, height: u32) -> &Self

Set scissor rectangle dynamically for a pass.

pub fn set_scissors<S>( &self, first_scissor: u32, scissors: impl IntoIterator<Item = S>, ) -> &Self

where S: Into<Rect2D>,

Set scissor rectangles dynamically for a pass.

pub fn set_viewport( &self, x: f32, y: f32, width: f32, height: f32, depth: Range<f32>, ) -> &Self

Set the viewport dynamically for a pass.

pub fn set_viewports<V>( &self, first_viewport: u32, viewports: impl IntoIterator<Item = V>, ) -> &Self

where V: Into<Viewport>,

Set the viewports dynamically for a pass.