gfx 0.9.1

A high-performance, bindless graphics API
Documentation 
1
2
3
4
5
6
7
8
9
10
11
12
13
14
15
16
17
18
19
20
21
22
23
24
25
26
27
28
29
30
31
32
33
34
35
36
37
38
39
40
41
42
43
44
45
46
47
48
49
50
51
52
53
54
55
56
57
58
59
60
61
62
63
64
65
66
67
68
69
70
71
72
73
74
75
76
77
78
79
80
81
82
83
84
85
86
87
88
89
90
91
92
93
94
95
96
97
98
99
100
101
102
103
104
105
106
107
108
109
110
111
112
113
114
115
116
117
118
119
120
121
122
123
124
125
126
127
128
129
130
131
132
133
134
135
136
137
138
139
140
141
142
143
144
145
146
147
148
149
150
151
152
153
154
155
156
157
158
159
160
161
162
163
164
165
166
167
168
169
170
171
172
173
174
175
176
177
178
179
180
181
182
183
184
185
186
187
188
189
190
191
192
193
194
195
196
197
198
199
200
201
202
203
204
205
206
207
208
209
210
211
212
213
214
215
216
217
218
219
220
221
222
223
224
225
226
227
228
229
230
231
232
233
234
235
236
237
238
239
240
241
242
243

// Copyright 2014 The Gfx-rs Developers.
//
// Licensed under the Apache License, Version 2.0 (the "License");
// you may not use this file except in compliance with the License.
// You may obtain a copy of the License at
//
//     http://www.apache.org/licenses/LICENSE-2.0
//
// Unless required by applicable law or agreed to in writing, software
// distributed under the License is distributed on an "AS IS" BASIS,
// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
// See the License for the specific language governing permissions and
// limitations under the License.

//! Graphics commands encoder.

#![deny(missing_docs)]

use std::mem;
use draw_state::target::{Depth, Stencil};

use gfx_core::{Device, Factory, IndexType, Resources, SubmitInfo, VertexCount};
use gfx_core::{draw, format, handle, tex};
use gfx_core::factory::Phantom;
use mesh;
use pso;


/// An error occuring in buffer/texture updates.
#[allow(missing_docs)]
#[derive(Clone, Debug, PartialEq)]
pub enum UpdateError<T> {
    OutOfBounds {
        target: T,
        source: T,
    },
    UnitCountMismatch {
        target: usize,
        slice: usize,
    },
}


/// Graphics commands encoder.
pub struct Encoder<R: Resources, C: draw::CommandBuffer<R>> {
    command_buffer: C,
    data_buffer: draw::DataBuffer,
    handles: handle::Manager<R>,
}

impl<R: Resources, C: draw::CommandBuffer<R>> Encoder<R, C> {
    /// Create a new encoder using a factory.
    pub fn create<F>(factory: &mut F) -> Encoder<R, C> where
        F: Factory<R, CommandBuffer = C>
    {
        Encoder {
            command_buffer: factory.create_command_buffer(),
            data_buffer: draw::DataBuffer::new(),
            handles: handle::Manager::new(),
        }
    }

    /// Reset all commands for the command buffer re-usal.
    pub fn reset(&mut self) {
        self.command_buffer.reset();
        self.data_buffer.clear();
        self.handles.clear();
    }

    /// Get command and data buffers to be submitted to the device.
    pub fn as_buffer<D>(&self) -> SubmitInfo<D> where
        D: Device<Resources=R, CommandBuffer=C> {
        SubmitInfo(&self.command_buffer, &self.data_buffer, &self.handles)
    }

    /// Clone the renderer shared data but ignore the commands.
    pub fn clone_empty(&self) -> Encoder<R, C> {
        Encoder {
            command_buffer: self.command_buffer.clone_empty(),
            data_buffer: draw::DataBuffer::new(),
            handles: handle::Manager::new(),
        }
    }

    /// Update a buffer with a slice of data.
    pub fn update_buffer<T: Copy>(&mut self, buf: &handle::Buffer<R, T>,
                         data: &[T], offset_elements: usize)
                         -> Result<(), UpdateError<usize>>
    {
        if data.is_empty() {
            return Ok(())
        }
        let elem_size = mem::size_of::<T>();
        let offset_bytes = elem_size * offset_elements;
        let bound = data.len().wrapping_mul(elem_size) + offset_bytes;
        if bound <= buf.get_info().size {
            let pointer = self.data_buffer.add_vec(data);
            self.command_buffer.update_buffer(
                self.handles.ref_buffer(buf.raw()).clone(),
                pointer, offset_bytes);
            Ok(())
        } else {
            Err(UpdateError::OutOfBounds {
                target: bound,
                source: buf.get_info().size,
            })
        }
    }

    /// Update a buffer with a single structure.
    pub fn update_constant_buffer<T: Copy>(&mut self, buf: &handle::Buffer<R, T>, data: &T) {
        let pointer = self.data_buffer.add_struct(data);
        self.command_buffer.update_buffer(
            self.handles.ref_buffer(buf.raw()).clone(),
            pointer, 0);
    }

    /// Update the contents of a texture.
    pub fn update_texture<S, T>(&mut self, tex: &handle::Texture<R, T>,
                          face: Option<tex::CubeFace>,
                          img: tex::NewImageInfo, data: &[S::DataType])
                          -> Result<(), UpdateError<[tex::Size; 3]>>
    where
        S: format::SurfaceTyped,
        S::DataType: Copy,
        T: format::Formatted<Surface = S>,
    {
        if data.is_empty() {
            return Ok(())
        }

        let target_count = img.get_texel_count();
        if target_count != data.len() {
            return Err(UpdateError::UnitCountMismatch {
                target: target_count,
                slice: data.len(),
            })
        }

        let dim = tex.get_info().kind.get_dimensions();
        if !img.is_inside(dim) {
            let (w, h, d, _) = dim;
            return Err(UpdateError::OutOfBounds {
                target: [
                    img.xoffset + img.width,
                    img.yoffset + img.height,
                    img.zoffset + img.depth,
                ],
                source: [w, h, d],
            })
        }

        let pointer = self.data_buffer.add_vec(data);
        self.command_buffer.update_texture(
            self.handles.ref_texture(tex.raw()).clone(),
            tex.get_info().kind, face, pointer,
            img.convert(T::get_format()));
        Ok(())
    }

    fn draw_indexed<T>(&mut self, buf: &handle::Buffer<R, T>, ty: IndexType,
                     slice: &mesh::Slice<R>, base: VertexCount,
                     instances: draw::InstanceOption) {
        self.command_buffer.bind_index(self.handles.ref_buffer(buf.raw()).clone());
        self.command_buffer.call_draw_indexed(ty,
            slice.start, slice.end - slice.start, base, instances);
    }

    fn draw_slice(&mut self, slice: &mesh::Slice<R>, instances: draw::InstanceOption) {
        match slice.kind {
            mesh::SliceKind::Vertex => self.command_buffer.call_draw(
                slice.start, slice.end - slice.start, instances),
            mesh::SliceKind::Index8(ref buf, base) =>
                self.draw_indexed(buf, IndexType::U8, slice, base, instances),
            mesh::SliceKind::Index16(ref buf, base) =>
                self.draw_indexed(buf, IndexType::U16, slice, base, instances),
            mesh::SliceKind::Index32(ref buf, base) =>
                self.draw_indexed(buf, IndexType::U32, slice, base, instances),
        }
    }

    fn clear_all<T>(&mut self,
                 color: Option<(&handle::RenderTargetView<R, T>, draw::ClearColor)>,
                 depth: Option<(&handle::DepthStencilView<R, T>, Depth)>,
                 stencil: Option<(&handle::DepthStencilView<R, T>, Stencil)>)
    {
        use gfx_core::pso::PixelTargetSet;

        let mut pts = PixelTargetSet::new();
        pts.colors[0] = color.map(|(ref view, _)|
            self.handles.ref_rtv(view.raw()).clone());
        pts.depth = depth.map(|(ref view, _)|
            self.handles.ref_dsv(view.raw()).clone());
        pts.stencil = stencil.map(|(ref view, _)|
            self.handles.ref_dsv(view.raw()).clone());

        self.command_buffer.bind_pixel_targets(pts);

        self.command_buffer.clear(draw::ClearSet(
            [color.map(|(_, c)| c), None, None, None],
            depth.map(|(_, d)| d), stencil.map(|(_, s)| s)
        ));
    }

    /// Clear a target view with a specified value.
    pub fn clear<T: format::RenderFormat>(&mut self,
                 view: &handle::RenderTargetView<R, T>, value: T::View)
    where T::View: Into<draw::ClearColor> {
        self.clear_all(Some((view, value.into())), None, None)
    }
    /// Clear a depth view with a specified value.
    pub fn clear_depth<T: format::DepthFormat>(&mut self,
                       view: &handle::DepthStencilView<R, T>, depth: Depth) {
        self.clear_all(None, Some((view, depth)), None)
    }

    /// Clear a stencil view with a specified value.
    pub fn clear_stencil<T: format::StencilFormat>(&mut self,
                         view: &handle::DepthStencilView<R, T>, stencil: Stencil) {
        self.clear_all(None, None, Some((view, stencil)))
    }

    /// Draw a mesh slice using a typed pipeline state object (PSO).
    pub fn draw<D: pso::PipelineData<R>>(&mut self, slice: &mesh::Slice<R>,
                pipeline: &pso::PipelineState<R, D::Meta>, user_data: &D)
    {
        let (pso, _) = self.handles.ref_pso(pipeline.get_handle());
        self.command_buffer.bind_pipeline_state(pso.clone());
        let raw_data = user_data.bake(pipeline.get_meta(), &mut self.handles);
        self.command_buffer.bind_vertex_buffers(raw_data.vertex_buffers);
        self.command_buffer.bind_constant_buffers(raw_data.constant_buffers);
        for &(location, value) in &raw_data.global_constants {
            self.command_buffer.bind_global_constant(location, value);
        }
        self.command_buffer.bind_resource_views(raw_data.resource_views);
        self.command_buffer.bind_unordered_views(raw_data.unordered_views);
        self.command_buffer.bind_samplers(raw_data.samplers);
        self.command_buffer.bind_pixel_targets(raw_data.pixel_targets);
        self.command_buffer.set_ref_values(raw_data.ref_values);
        self.command_buffer.set_scissor(raw_data.scissor);
        self.draw_slice(slice, slice.instances);
    }
}