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
244
245
246
247
248
249
250
251
252
253
254
255
256
257
258
259
260
261
262
263
264
265
266
267
268
269
270
271
272
273
274
275
276
277
278
279
280
281
282
283
284
285
286
287
288
289
290
291
292
293
294
295
296
297
298
299
300
301
302
303
304
305
306
307
308
309
310
311
312
313
314
315
316
317
318
319
320
321
322
323
324
325
326
327
328
329
330
331
332
333
334
335
336
337
338
339
340
341
342
343
344
345
346
347
348
349
350
351
352
353
354
355
356
357
358
359
360
361
362
363
364
365
366
367
368
369
370
371
372
373
374
375
376
377
378
379
380
381
382
383
384
385
386
387
388
389
390
391
392
393
394
395
396
397
398
399
400
401
402
403
404
405
406
407
408
409
410
411
412
413
414
415
416
417
418
419
420
421
422
423
424
425
426
427
428
429
430
431
432
433
434
435
436
437
438
439
440
441
442
443
444
445
446
447
448
449
450
451
452
453
454
455
456
457
458
459
460
461
462
463
464
465
466
467
468
469
470
471
472
473
474
475
476
477
478
479
480
481
482
483
484
485
486
487
488
489
490
491
492
493
494
495
496
497
498
499
500
501
502
503
504
505
506
507
508
509
510
511
512
513
514
515
516
517
518
519
520
521
522
523
524
525
526
527
528
529
530
531
532
533
534
535
536
#![deny(missing_debug_implementations, missing_docs, unused)]

//! Low-level graphics abstraction for Rust. Mostly operates on data, not types.
//! Designed for use by libraries and higher-level abstractions only.

#[macro_use]
extern crate bitflags;
#[macro_use]
extern crate failure;

#[cfg(feature = "mint")]
extern crate mint;

#[cfg(feature = "serde")]
#[macro_use]
extern crate serde;

use std::any::Any;
use std::error::Error;
use std::fmt;
use std::hash::Hash;

//TODO: reconsider what is publicly exported

pub use self::adapter::{
    Adapter, AdapterInfo, MemoryProperties, MemoryType, MemoryTypeId, PhysicalDevice, QueuePriority,
};
pub use self::device::Device;
pub use self::pool::CommandPool;
pub use self::pso::DescriptorPool;
pub use self::queue::{
    Capability, CommandQueue, Compute, General, Graphics, QueueFamily, QueueGroup, QueueType,
    Submission, Supports, Transfer,
};
pub use self::window::{
    AcquireError, CompositeAlpha, PresentMode, Surface, SurfaceCapabilities,
    SwapImageIndex, Swapchain, SwapchainConfig,
};

pub mod adapter;
pub mod buffer;
pub mod command;
pub mod device;
pub mod error;
pub mod format;
pub mod image;
pub mod mapping;
pub mod memory;
pub mod pass;
pub mod pool;
pub mod pso;
pub mod query;
pub mod queue;
pub mod range;
pub mod window;

#[doc(hidden)]
pub mod backend;

/// Draw vertex count.
pub type VertexCount = u32;
/// Draw vertex base offset.
pub type VertexOffset = i32;
/// Draw number of indices.
pub type IndexCount = u32;
/// Draw number of instances.
pub type InstanceCount = u32;
/// Indirect draw calls count.
pub type DrawCount = u32;
/// Number of vertices in a patch
pub type PatchSize = u8;
/// Number of work groups.
pub type WorkGroupCount = [u32; 3];

/// Slot for an attribute.
pub type AttributeSlot = u8;
/// Slot for a constant buffer object.
pub type ConstantBufferSlot = u8;
/// Slot for a shader resource view.
pub type ResourceViewSlot = u8;
/// Slot for an unordered access object.
pub type UnorderedViewSlot = u8;
/// Slot for an active color buffer.
pub type ColorSlot = u8;
/// Slot for a sampler.
pub type SamplerSlot = u8;

bitflags! {
    /// Features that the device supports.
    /// These only include features of the core interface and not API extensions.
    #[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
    pub struct Features: u64 {
        /// Bit mask of Vulkan Core features.
        const CORE_MASK   = 0x0FFF_FFFF_FFFF_FFFF;
        /// Bit mask of Vulkan Portability features.
        const PORTABILITY_MASK  = 0xF000_0000_0000_0000;

        /// Support for robust buffer access.
        /// Buffer access by SPIR-V shaders is checked against the buffer/image boundaries.
        const ROBUST_BUFFER_ACCESS = 0x000_0000_0000_0001;
        /// Support the full 32-bit range of indexed for draw calls.
        /// If not supported, the maximum index value is determined by `Limits::max_draw_index_value`.
        const FULL_DRAW_INDEX_U32 = 0x000_0000_0000_0002;
        /// Support cube array image views.
        const IMAGE_CUBE_ARRAY = 0x000_0000_0000_0004;
        /// Support different color blending settings per attachments on graphics pipeline creation.
        const INDEPENDENT_BLENDING = 0x000_0000_0000_0008;
        /// Support geometry shader.
        const GEOMETRY_SHADER = 0x000_0000_0000_0010;
        /// Support tessellation shaders.
        const TESSELLATION_SHADER = 0x000_0000_0000_0020;
        /// Support per-sample shading and multisample interpolation.
        const SAMPLE_RATE_SHADING = 0x000_0000_0000_0040;
        /// Support dual source blending.
        const DUAL_SRC_BLENDING = 0x000_0000_0000_0080;
        /// Support logic operations.
        const LOGIC_OP = 0x000_0000_0000_0100;
        /// Support multiple draws per indirect call.
        const MULTI_DRAW_INDIRECT = 0x000_0000_0000_0200;
        /// Support indirect drawing with first instance value.
        /// If not supported the first instance value **must** be 0.
        const DRAW_INDIRECT_FIRST_INSTANCE = 0x00_0000_0000_0400;
        /// Support depth clamping.
        const DEPTH_CLAMP = 0x000_0000_0000_0800;
        /// Support depth bias clamping.
        const DEPTH_BIAS_CLAMP = 0x000_0000_0000_1000;
        /// Support non-fill polygon modes.
        const NON_FILL_POLYGON_MODE = 0x000_0000_0000_2000;
        /// Support depth bounds test.
        const DEPTH_BOUNDS = 0x000_0000_0000_4000;
        /// Support lines with width other than 1.0.
        const LINE_WIDTH = 0x000_0000_0000_8000;
        /// Support points with size greater than 1.0.
        const POINT_SIZE = 0x000_0000_0001_0000;
        /// Support replacing alpha values with 1.0.
        const ALPHA_TO_ONE = 0x000_0000_0002_0000;
        /// Support multiple viewports and scissors.
        const MULTI_VIEWPORTS = 0x000_0000_0004_0000;
        /// Support anisotropic filtering.
        const SAMPLER_ANISOTROPY = 0x000_0000_0008_0000;
        /// Support ETC2 texture compression formats.
        const FORMAT_ETC2 = 0x000_0000_0010_0000;
        /// Support ASTC (LDR) texture compression formats.
        const FORMAT_ASTC_LDR = 0x000_0000_0020_0000;
        /// Support BC texture compression formats.
        const FORMAT_BC = 0x000_0000_0040_0000;
        /// Support precise occlusion queries, returning the actual number of samples.
        /// If not supported, queries return a non-zero value when at least **one** sample passes.
        const PRECISE_OCCLUSION_QUERY = 0x000_0000_0080_0000;
        /// Support query of pipeline statistics.
        const PIPELINE_STATISTICS_QUERY = 0x000_0000_0100_0000;
        /// Support unordered access stores and atomic ops in the vertex, geometry
        /// and tessellation shader stage.
        /// If not supported, the shader resources **must** be annotated as read-only.
        const VERTEX_STORES_AND_ATOMICS = 0x000_0000_0200_0000;
        /// Support unordered access stores and atomic ops in the fragment shader stage
        /// If not supported, the shader resources **must** be annotated as read-only.
        const FRAGMENT_STORES_AND_ATOMICS = 0x000_0000_0400_0000;
        ///
        const SHADER_TESSELLATION_AND_GEOMETRY_POINT_SIZE = 0x000_0000_0800_0000;
        ///
        const SHADER_IMAGE_GATHER_EXTENDED = 0x000_0000_1000_0000;
        ///
        const SHADER_STORAGE_IMAGE_EXTENDED_FORMATS = 0x000_0000_2000_0000;
        ///
        const SHADER_STORAGE_IMAGE_MULTISAMPLE = 0x000_0000_4000_0000;
        ///
        const SHADER_STORAGE_IMAGE_READ_WITHOUT_FORMAT = 0x000_0000_8000_0000;
        ///
        const SHADER_STORAGE_IMAGE_WRITE_WITHOUT_FORMAT = 0x000_0001_0000_0000;
        ///
        const SHADER_UNIFORM_BUFFER_ARRAY_DYNAMIC_INDEXING = 0x000_0002_0000_0000;
        ///
        const SHADER_SAMPLED_IMAGE_ARRAY_DYNAMIC_INDEXING = 0x000_0004_0000_0000;
        ///
        const SHADER_STORAGE_BUFFER_ARRAY_DYNAMIC_INDEXING = 0x000_0008_0000_0000;
        ///
        const SHADER_STORAGE_IMAGE_ARRAY_DYNAMIC_INDEXING = 0x000_0010_0000_0000;
        ///
        const SHADER_CLIP_DISTANCE = 0x000_0020_0000_0000;
        ///
        const SHADER_CULL_DISTANCE = 0x000_0040_0000_0000;
        ///
        const SHADER_FLOAT64 = 0x000_0080_0000_0000;
        ///
        const SHADER_INT64 = 0x000_0100_0000_0000;
        ///
        const SHADER_INT16 = 0x000_0200_0000_0000;
        ///
        const SHADER_RESOURCE_RESIDENCY = 0x000_0400_0000_0000;
        ///
        const SHADER_RESOURCE_MIN_LOD = 0x000_0800_0000_0000;
        ///
        const SPARSE_BINDING = 0x000_1000_0000_0000;
        ///
        const SPARSE_RESIDENCY_BUFFER = 0x000_2000_0000_0000;
        ///
        const SPARSE_RESIDENCY_IMAGE_2D = 0x000_4000_0000_0000;
        ///
        const SPARSE_RESIDENCY_IMAGE_3D = 0x000_8000_0000_0000;
        ///
        const SPARSE_RESIDENCY_2_SAMPLES = 0x001_0000_0000_0000;
        ///
        const SPARSE_RESIDENCY_4_SAMPLES = 0x002_0000_0000_0000;
        ///
        const SPARSE_RESIDENCY_8_SAMPLES = 0x004_0000_0000_0000;
        ///
        const SPARSE_RESIDENCY_16_SAMPLES = 0x008_0000_0000_0000;
        ///
        const SPARSE_RESIDENCY_ALIASED = 0x010_0000_0000_0000;
        ///
        const VARIABLE_MULTISAMPLE_RATE = 0x020_0000_0000_0000;
        ///
        const INHERITED_QUERIES = 0x040_0000_0000_0000;

        /// Support triangle fan primitive topology.
        const TRIANGLE_FAN = 0x1000_0000_0000_0000;
        /// Support separate stencil reference values for front and back sides.
        const SEPARATE_STENCIL_REF_VALUES = 0x2000_0000_0000_0000;
        /// Support manually specified vertex attribute rates (divisors).
        const INSTANCE_RATE = 0x4000_0000_0000_0000;
        /// Support non-zero mipmap bias on samplers.
        const SAMPLER_MIP_LOD_BIAS = 0x8000_0000_0000_0000;
    }
}

/// Resource limits of a particular graphics device.
#[derive(Clone, Copy, Debug, Default, PartialEq)]
#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
pub struct Limits {
    /// Maximum supported image 1D size.
    pub max_image_1d_size: image::Size,
    /// Maximum supported image 2D size.
    pub max_image_2d_size: image::Size,
    /// Maximum supported image 3D size.
    pub max_image_3d_size: image::Size,
    /// Maximum supported image cube size.
    pub max_image_cube_size: image::Size,
    /// Maximum supporter image array size.
    pub max_image_array_layers: image::Layer,
    /// Maximum number of elements for the BufferView to see.
    pub max_texel_elements: usize,
    ///
    pub max_uniform_buffer_range: buffer::Offset,
    ///
    pub max_storage_buffer_range: buffer::Offset,
    ///
    pub max_push_constants_size: usize,
    ///
    pub max_memory_allocation_count: usize,
    ///
    pub max_sampler_allocation_count: usize,
    ///
    pub max_bound_descriptor_sets: pso::DescriptorSetIndex,

    ///
    pub max_per_stage_descriptor_samplers: usize,
    ///
    pub max_per_stage_descriptor_uniform_buffers: usize,
    ///
    pub max_per_stage_descriptor_storage_buffers: usize,
    ///
    pub max_per_stage_descriptor_sampled_images: usize,
    ///
    pub max_per_stage_descriptor_storage_images: usize,
    ///
    pub max_per_stage_descriptor_input_attachments: usize,
    ///
    pub max_per_stage_resources: usize,

    ///
    pub max_descriptor_set_samplers: usize,
    ///
    pub max_descriptor_set_uniform_buffers: usize,
    ///
    pub max_descriptor_set_uniform_buffers_dynamic: usize,
    ///
    pub max_descriptor_set_storage_buffers: usize,
    ///
    pub max_descriptor_set_storage_buffers_dynamic: usize,
    ///
    pub max_descriptor_set_sampled_images: usize,
    ///
    pub max_descriptor_set_storage_images: usize,
    ///
    pub max_descriptor_set_input_attachments: usize,

    /// Maximum number of vertex input attributes that can be specified for a graphics pipeline.
    pub max_vertex_input_attributes: usize,
    /// Maximum number of vertex buffers that can be specified for providing vertex attributes to a graphics pipeline.
    pub max_vertex_input_bindings: usize,
    /// Maximum vertex input attribute offset that can be added to the vertex input binding stride.
    pub max_vertex_input_attribute_offset: usize,
    /// Maximum vertex input binding stride that can be specified in a vertex input binding.
    pub max_vertex_input_binding_stride: usize,
    /// Maximum number of components of output variables which can be output by a vertex shader.
    pub max_vertex_output_components: usize,

    /// Maximum number of vertices for each patch.
    pub max_patch_size: PatchSize,
    ///
    pub max_geometry_shader_invocations: usize,
    ///
    pub max_geometry_input_components: usize,
    ///
    pub max_geometry_output_components: usize,
    ///
    pub max_geometry_output_vertices: usize,
    ///
    pub max_geometry_total_output_components: usize,
    ///
    pub max_fragment_input_components: usize,
    ///
    pub max_fragment_output_attachments: usize,
    ///
    pub max_fragment_dual_source_attachments: usize,
    ///
    pub max_fragment_combined_output_resources: usize,

    ///
    pub max_compute_shared_memory_size: usize,
    ///
    pub max_compute_work_group_count: WorkGroupCount,
    ///
    pub max_compute_work_group_invocations: usize,
    ///
    pub max_compute_work_group_size: [u32; 3],

    ///
    pub max_draw_indexed_index_value: IndexCount,
    ///
    pub max_draw_indirect_count: InstanceCount,

    ///
    pub max_sampler_lod_bias: f32,
    /// Maximum degree of sampler anisotropy.
    pub max_sampler_anisotropy: f32,

    /// Maximum number of viewports.
    pub max_viewports: usize,
    ///
    pub max_viewport_dimensions: [image::Size; 2],
    ///
    pub max_framebuffer_extent: image::Extent,

    ///
    pub min_memory_map_alignment: usize,
    ///
    pub buffer_image_granularity: buffer::Offset,
    /// The alignment of the start of buffer used as a texel buffer, in bytes, non-zero.
    pub min_texel_buffer_offset_alignment: buffer::Offset,
    /// The alignment of the start of buffer used for uniform buffer updates, in bytes, non-zero.
    pub min_uniform_buffer_offset_alignment: buffer::Offset,
    /// The alignment of the start of buffer used as a storage buffer, in bytes, non-zero.
    pub min_storage_buffer_offset_alignment: buffer::Offset,
    /// Number of samples supported for color attachments of framebuffers (floating/fixed point).
    pub framebuffer_color_samples_count: image::NumSamples,
    /// Number of samples supported for depth attachments of framebuffers.
    pub framebuffer_depth_samples_count: image::NumSamples,
    /// Number of samples supported for stencil attachments of framebuffers.
    pub framebuffer_stencil_samples_count: image::NumSamples,
    /// Maximum number of color attachments that can be used by a subpass in a render pass.
    pub max_color_attachments: usize,
    ///
    pub standard_sample_locations: bool,
    /// The alignment of the start of the buffer used as a GPU copy source, in bytes, non-zero.
    pub optimal_buffer_copy_offset_alignment: buffer::Offset,
    /// The alignment of the row pitch of the texture data stored in a buffer that is
    /// used in a GPU copy operation, in bytes, non-zero.
    pub optimal_buffer_copy_pitch_alignment: buffer::Offset,
    /// Size and alignment in bytes that bounds concurrent access to host-mapped device memory.
    pub non_coherent_atom_size: usize,

    /// The alignment of the vertex buffer stride.
    pub min_vertex_input_binding_stride_alignment: buffer::Offset,
}

/// Describes the type of geometric primitives,
/// created from vertex data.
#[derive(Clone, Copy, Debug, Eq, Hash, PartialEq, PartialOrd, Ord)]
#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
#[repr(u8)]
pub enum Primitive {
    /// Each vertex represents a single point.
    PointList,
    /// Each pair of vertices represent a single line segment. For example, with `[a, b, c, d,
    /// e]`, `a` and `b` form a line, `c` and `d` form a line, and `e` is discarded.
    LineList,
    /// Every two consecutive vertices represent a single line segment. Visually forms a "path" of
    /// lines, as they are all connected. For example, with `[a, b, c]`, `a` and `b` form a line
    /// line, and `b` and `c` form a line.
    LineStrip,
    /// Each triplet of vertices represent a single triangle. For example, with `[a, b, c, d, e]`,
    /// `a`, `b`, and `c` form a triangle, `d` and `e` are discarded.
    TriangleList,
    /// Every three consecutive vertices represent a single triangle. For example, with `[a, b, c,
    /// d]`, `a`, `b`, and `c` form a triangle, and `b`, `c`, and `d` form a triangle.
    TriangleStrip,
    /// Each quadtruplet of vertices represent a single line segment with adjacency information.
    /// For example, with `[a, b, c, d]`, `b` and `c` form a line, and `a` and `d` are the adjacent
    /// vertices.
    LineListAdjacency,
    /// Every four consecutive vertices represent a single line segment with adjacency information.
    /// For example, with `[a, b, c, d, e]`, `[a, b, c, d]` form a line segment with adjacency, and
    /// `[b, c, d, e]` form a line segment with adjacency.
    LineStripAdjacency,
    /// Each sextuplet of vertices represent a single triangle with adjacency information. For
    /// example, with `[a, b, c, d, e, f]`, `a`, `c`, and `e` form a triangle, and `b`, `d`, and
    /// `f` are the adjacent vertices, where `b` is adjacent to the edge formed by `a` and `c`, `d`
    /// is adjacent to the edge `c` and `e`, and `f` is adjacent to the edge `e` and `a`.
    TriangleListAdjacency,
    /// Every even-numbered vertex (every other starting from the first) represents an additional
    /// vertex for the triangle strip, while odd-numbered vertices (every other starting from the
    /// second) represent adjacent vertices. For example, with `[a, b, c, d, e, f, g, h]`, `[a, c,
    /// e, g]` form a triangle strip, and `[b, d, f, h]` are the adjacent vertices, where `b`, `d`,
    /// and `f` are adjacent to the first triangle in the strip, and `d`, `f`, and `h` are adjacent
    /// to the second.
    TriangleStripAdjacency,
    /// Patch list,
    /// used with shaders capable of producing primitives on their own (tessellation)
    PatchList(PatchSize),
}

/// An enum describing the type of an index value in a slice's index buffer
#[allow(missing_docs)]
#[derive(Clone, Copy, Debug, Eq, Hash, Ord, PartialEq, PartialOrd)]
#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
#[repr(u8)]
pub enum IndexType {
    U16,
    U32,
}

/// An instantiated backend.
///
/// Any startup the backend needs to perform will be done when creating the type that implements
/// `Instance`.
///
/// # Examples
///
/// ```rust
/// # extern crate gfx_backend_empty;
/// # extern crate gfx_hal;
/// use gfx_backend_empty as backend;
/// use gfx_hal as hal;
///
/// // Create a concrete instance of our backend (this is backend-dependent and may be more
/// // complicated for some backends).
/// let instance = backend::Instance;
/// // We can get a list of the available adapters, which are either physical graphics
/// // devices, or virtual adapters. Because we are using the dummy `empty` backend,
/// // there will be nothing in this list.
/// for (idx, adapter) in hal::Instance::enumerate_adapters(&instance).iter().enumerate() {
///     println!("Adapter {}: {:?}", idx, adapter.info);
/// }
/// ```
pub trait Instance: Any + Send + Sync {
    /// Associated backend type of this instance.
    type Backend: Backend;
    /// Return all available adapters.
    fn enumerate_adapters(&self) -> Vec<Adapter<Self::Backend>>;
}

/// The `Backend` trait wraps together all the types needed
/// for a graphics backend. Each backend module, such as OpenGL
/// or Metal, will implement this trait with its own concrete types.
#[allow(missing_docs)]
pub trait Backend: 'static + Sized + Eq + Clone + Hash + fmt::Debug + Any + Send + Sync {
    //type Instance:          Instance<Self>;
    type PhysicalDevice: PhysicalDevice<Self>;
    type Device: Device<Self>;

    type Surface: Surface<Self>;
    type Swapchain: Swapchain<Self>;

    type QueueFamily: QueueFamily;
    type CommandQueue: queue::RawCommandQueue<Self>;
    type CommandBuffer: command::RawCommandBuffer<Self>;

    type ShaderModule: fmt::Debug + Any + Send + Sync;
    type RenderPass: fmt::Debug + Any + Send + Sync;
    type Framebuffer: fmt::Debug + Any + Send + Sync;

    type Memory: fmt::Debug + Any + Send + Sync;
    type CommandPool: pool::RawCommandPool<Self>;

    type Buffer: fmt::Debug + Any + Send + Sync;
    type BufferView: fmt::Debug + Any + Send + Sync;
    type Image: fmt::Debug + Any + Send + Sync;
    type ImageView: fmt::Debug + Any + Send + Sync;
    type Sampler: fmt::Debug + Any + Send + Sync;

    type ComputePipeline: fmt::Debug + Any + Send + Sync;
    type GraphicsPipeline: fmt::Debug + Any + Send + Sync;
    type PipelineCache: fmt::Debug + Any + Send + Sync;
    type PipelineLayout: fmt::Debug + Any + Send + Sync;
    type DescriptorPool: pso::DescriptorPool<Self>;
    type DescriptorSet: fmt::Debug + Any + Send + Sync;
    type DescriptorSetLayout: fmt::Debug + Any + Send + Sync;

    type Fence: fmt::Debug + Any + Send + Sync;
    type Semaphore: fmt::Debug + Any + Send + Sync;
    type QueryPool: fmt::Debug + Any + Send + Sync;
}

/// Marks that an error occurred submitting a command to a command buffer.
#[derive(Clone, Debug, PartialEq)]
#[cfg_attr(feature = "serde", derive(Serialize, Deserialize))]
pub enum SubmissionError {}

impl fmt::Display for SubmissionError {
    fn fmt(&self, f: &mut fmt::Formatter) -> fmt::Result {
        write!(f, "{}", self.description())
    }
}

impl Error for SubmissionError {
    fn description(&self) -> &str {
        "Submission error"
    }
}

/// Submission result for DX11 backend.  Currently mostly unused.
pub type SubmissionResult<T> = Result<T, SubmissionError>;

/// Represents a combination of a logical device and the
/// hardware queues it provides.
///
/// This structure is typically created using an `Adapter`.
#[derive(Debug)]
pub struct Gpu<B: Backend> {
    /// Logical device for a given backend.
    pub device: B::Device,
    /// The command queues that the device provides.
    pub queues: queue::Queues<B>,
}