ash-tray 0.2.1

A Tray to host Ash with Winit
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
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
537
538
539
540
541
542
543
544
545
546
547
548
549
550
551
552
553
554
555
556
557
558
559
560
561
562
563
564
565
566
567
568
569
570
571
572
573
574
575
576
577
578
579
580
581
582
583
584
585
586
587
588
589
590
591
592
593
594
595
596
597
598
599
600
601
602
603
604
605
606
607
608
609
610
611
612
613
614
615
616
617
618
619
620
621
622
623
624
625
626
627
628
629
630
631
632
633
634
635
636
637
638
639
640
641
642
643
644
645
646
647
648
649
650
651
652
653
654
655
//    Copyright 2019 Michael Mestnik

//    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.

use memoffset::offset_of;
use std::cell::{Cell, RefCell};
use std::ffi::CStr;
use std::mem;
use std::os::raw::c_uchar;
use std::slice;

// use crate::ash::version::DeviceV1_0;
// use crate::ash::{vk, Device, Instance};
use crate::ash::prelude::VkResult;
use crate::imgui::{FrameSize, ImDrawIdx, ImDrawVert, ImGui, Ui};
use crate::vk_helper::*;
use crate::vk_mem::{AllocationCreateFlags, AllocationCreateInfo};

use glsl_to_spirv_macros::{glsl_fs, glsl_vs};
use glsl_to_spirv_macros_impl::GLSLEmbedImpl;

pub struct Renderer {
    pipeline_layout: PipelineLayout,
    vertex_shader: ShaderModule,
    fragment_shader: ShaderModule,
    render_pass: RefCell<Option<RenderPass>>,
    pipeline: RefCell<Option<crate::ash::vk::Pipeline>>,
    old_pipeline: RefCell<Option<crate::ash::vk::Pipeline>>,
    vertex_buffers: [Buffer; Renderer::FRAME_COUNT],
    index_buffers: [Buffer; Renderer::FRAME_COUNT],
    image_buffer: RefCell<Buffer>,
    image_width: u32,
    image_height: u32,
    image: RefCell<Image>,
    image_view: ImageView,
    sampler: Sampler,
    descriptor_set: DescriptorSet,
    frame_index: RefCell<usize>,
    image_is_valid: Cell<bool>,
}

impl Renderer {
    const QUAD_COUNT_PER_FRAME: usize = 64 * 1024;
    const VERTEX_COUNT_PER_FRAME: usize = 4 * Renderer::QUAD_COUNT_PER_FRAME;
    const INDEX_COUNT_PER_FRAME: usize = 6 * Renderer::QUAD_COUNT_PER_FRAME;
    const PUSH_CONSTANT_SIZE: usize = 8;
    const FRAME_COUNT: usize = 2;

    pub fn new_simple(
        instance: &Instance,
        physical_device: crate::ash::vk::PhysicalDevice,
        device: &Device,
        imgui: &mut ImGui,
    ) -> VkResult<Self> {
        let allocator = Allocator::new(&instance, physical_device, &device).map_err(|e| {
            if let vk_mem::ErrorKind::Vulkan(e) = e.kind() {
                crate::ash::vk::Result::from_raw(e.as_raw())
            } else {
                /* Tempted to just call Err(()).unwrap() */
                crate::ash::vk::Result::from_raw(-1)
            }
        })?;

        Self::new(device, &allocator, imgui)
    }

    pub fn new(device: &Device, allocator: &Allocator, imgui: &mut ImGui) -> VkResult<Self> {
        use arrayvec::ArrayVec;

        let vertex_shader = ShaderModule::new_simple(
            &device,
            glsl_vs! { r#"#version 430 core

layout(location = 0) in vec2 a_pos;
layout(location = 1) in vec2 a_uv;
layout(location = 2) in vec4 a_col;

layout(push_constant) uniform push_t {
    vec2 g_dims_rcp;
};

out gl_PerVertex {
    vec4 gl_Position;
};

layout(location = 0) out vec2 v_uv;
layout(location = 1) out vec4 v_col;

void main() {
    gl_Position = vec4(a_pos*g_dims_rcp*2.0 - 1.0, 0, 1);
    v_uv = a_uv;
    v_col = a_col;
}"# },
        )?;

        let fragment_shader = ShaderModule::new_simple(
            &device,
            glsl_fs! { r#"#version 430 core



layout(location = 0) in vec2 v_uv;
layout(location = 1) in vec4 v_col;

layout(set = 0, binding = 0) uniform sampler2D g_tex;

layout(location = 0) out vec4 o_col;

void main() {
    o_col = v_col*texture(g_tex, v_uv);
}"# },
        )?;

        let sampler = Sampler::new(
            &device,
            &crate::ash::vk::SamplerCreateInfo::builder()
                .mag_filter(crate::ash::vk::Filter::LINEAR)
                .min_filter(crate::ash::vk::Filter::LINEAR),
        )?;

        let binding = crate::ash::vk::DescriptorSetLayoutBinding::builder()
            .descriptor_type(crate::ash::vk::DescriptorType::COMBINED_IMAGE_SAMPLER)
            .descriptor_count(1)
            .stage_flags(crate::ash::vk::ShaderStageFlags::FRAGMENT)
            .immutable_samplers(slice::from_ref(&sampler));
        let create_info =
            crate::ash::vk::DescriptorSetLayoutCreateInfo::builder().bindings(slice::from_ref(&binding));

        let descriptor_set_layout = DescriptorSetLayout::new(&device, &create_info)?;

        let push_constant_range = crate::ash::vk::PushConstantRange {
            stage_flags: crate::ash::vk::ShaderStageFlags::VERTEX,
            offset: 0,
            size: Renderer::PUSH_CONSTANT_SIZE as u32,
        };
        let create_info = crate::ash::vk::PipelineLayoutCreateInfo::builder()
            .push_constant_ranges(slice::from_ref(&push_constant_range));

        let pipeline_layout =
            PipelineLayout::new(&device, slice::from_ref(&descriptor_set_layout), create_info)?;

        let vertex_buffers = {
            let create_info = crate::ash::vk::BufferCreateInfo::builder()
                .size(
                    (Renderer::VERTEX_COUNT_PER_FRAME * mem::size_of::<ImDrawVert>())
                        as crate::ash::vk::DeviceSize,
                )
                .usage(crate::ash::vk::BufferUsageFlags::VERTEX_BUFFER);

            let mut buffers = ArrayVec::<[Buffer; Renderer::FRAME_COUNT]>::new();
            for buffer in std::iter::repeat_with(|| {
                Buffer::new(
                    &allocator,
                    &create_info,
                    &AllocationCreateInfo {
                        usage: vk_mem::MemoryUsage::CpuOnly,
                        flags: AllocationCreateFlags::MAPPED,
                        ..Default::default()
                    },
                )
                .unwrap()
            }).take(Renderer::FRAME_COUNT) {
                buffers.push(buffer);
            };
            buffers.into_inner().unwrap()
        };

        let index_buffers = {
            let create_info = crate::ash::vk::BufferCreateInfo::builder()
                .size(
                    (Renderer::INDEX_COUNT_PER_FRAME * mem::size_of::<ImDrawIdx>())
                        as crate::ash::vk::DeviceSize,
                )
                .usage(crate::ash::vk::BufferUsageFlags::INDEX_BUFFER);

            let mut buffers = ArrayVec::<[Buffer; Renderer::FRAME_COUNT]>::new();
            for buffer in std::iter::repeat_with(|| {
                Buffer::new(
                    &allocator,
                    &create_info,
                    &AllocationCreateInfo {
                        usage: vk_mem::MemoryUsage::CpuOnly,
                        flags: AllocationCreateFlags::MAPPED,
                        ..Default::default()
                    },
                )
                .unwrap()
            }).take(Renderer::FRAME_COUNT) {
                buffers.push(buffer);
            };
            buffers.into_inner().unwrap()
        };

        let (image_width, image_height, image_pixels) =
            imgui.prepare_texture(|handle| (handle.width, handle.height, handle.pixels));

        let create_info = crate::ash::vk::BufferCreateInfo::builder()
            .size((image_width * image_height * 4) as crate::ash::vk::DeviceSize)
            .usage(crate::ash::vk::BufferUsageFlags::TRANSFER_SRC);

        let image_buffer = RefCell::new(Buffer::new(
            &allocator,
            &create_info,
            &AllocationCreateInfo {
                usage: vk_mem::MemoryUsage::CpuOnly,
                flags: AllocationCreateFlags::MAPPED,
                ..Default::default()
            },
        )?);

        let create_info = crate::ash::vk::ImageCreateInfo::builder()
            .image_type(crate::ash::vk::ImageType::TYPE_2D)
            .format(crate::ash::vk::Format::R8G8B8A8_UNORM)
            .extent(crate::ash::vk::Extent3D {
                width: image_width,
                height: image_height,
                depth: 1,
            })
            .mip_levels(1)
            .array_layers(1)
            .samples(crate::ash::vk::SampleCountFlags::TYPE_1)
            .usage(crate::ash::vk::ImageUsageFlags::SAMPLED | crate::ash::vk::ImageUsageFlags::TRANSFER_DST);

        let image = RefCell::new(Image::new(
            &allocator,
            &create_info,
            &AllocationCreateInfo {
                usage: vk_mem::MemoryUsage::GpuOnly,
                ..Default::default()
            },
        )?);

        let descriptor_pool_sizes = [crate::ash::vk::DescriptorPoolSize::builder()
            .ty(crate::ash::vk::DescriptorType::COMBINED_IMAGE_SAMPLER)
            .descriptor_count(1)
            .build()];

        let create_info = crate::ash::vk::DescriptorPoolCreateInfo::builder()
            .max_sets(1)
            .pool_sizes(&descriptor_pool_sizes);

        let descriptor_pool = DescriptorPool::new(&device, &create_info)?;

        let descriptor_set = DescriptorSet::new(
            &descriptor_pool,
            slice::from_ref(&descriptor_set_layout),
            crate::ash::vk::DescriptorSetAllocateInfo::builder(),
        )?[0]
            .clone();

        let create_info = crate::ash::vk::ImageViewCreateInfo::builder()
            .view_type(crate::ash::vk::ImageViewType::TYPE_2D)
            .format(crate::ash::vk::Format::R8G8B8A8_UNORM)
            .subresource_range(
                crate::ash::vk::ImageSubresourceRange::builder()
                    .aspect_mask(crate::ash::vk::ImageAspectFlags::COLOR)
                    .level_count(1)
                    .layer_count(1)
                    .build(),
            );

        let image_view = ImageView::new(&image.borrow(), create_info)?;

        {
            use crate::ash::version::DeviceV1_0;
            let image_info = crate::ash::vk::DescriptorImageInfo::builder()
                .sampler(**sampler)
                .image_view(**image_view)
                .image_layout(crate::ash::vk::ImageLayout::SHADER_READ_ONLY_OPTIMAL)
                .build();

            let write_descriptor_set = crate::ash::vk::WriteDescriptorSet::builder()
                .dst_set(**descriptor_set)
                .descriptor_type(crate::ash::vk::DescriptorType::COMBINED_IMAGE_SAMPLER)
                .image_info(slice::from_ref(&image_info));
            unsafe { device.update_descriptor_sets(slice::from_ref(&write_descriptor_set), &[]) };
        }

        let image_base = image_buffer.borrow().allocation_info.get_mapped_data() as *mut c_uchar;
        assert_eq!((image_width * image_height * 4) as usize, image_pixels.len());
        unsafe {
            image_base.copy_from_nonoverlapping(image_pixels.as_ptr(), image_pixels.len());
        };

        image_buffer.borrow().flush(0, 0).unwrap();

        Ok(Self {
            pipeline_layout,
            vertex_shader,
            fragment_shader,
            render_pass: Default::default(),
            pipeline: Default::default(),
            old_pipeline: Default::default(),
            vertex_buffers,
            index_buffers,
            image_buffer,
            image_width,
            image_height,
            image,
            image_view,
            sampler,
            descriptor_set,
            frame_index: Default::default(),
            image_is_valid: Default::default(),
        })
    }

    pub fn begin_frame(&self, command_buffer: &CommandBuffer) {
        if !self.image_is_valid.get() {
            use crate::ash::{version::DeviceV1_0, vk};
            let transfer_from_undef = vk::ImageMemoryBarrier::builder()
                .dst_access_mask(vk::AccessFlags::TRANSFER_WRITE)
                .new_layout(vk::ImageLayout::TRANSFER_DST_OPTIMAL)
                .src_queue_family_index(vk::QUEUE_FAMILY_IGNORED)
                .dst_queue_family_index(vk::QUEUE_FAMILY_IGNORED)
                .image(***self.image.borrow())
                .subresource_range(
                    vk::ImageSubresourceRange::builder()
                        .aspect_mask(vk::ImageAspectFlags::COLOR)
                        .level_count(1)
                        .layer_count(1)
                        .build(),
                );

            unsafe {
                command_buffer.command_pool.device.cmd_pipeline_barrier(
                    ***command_buffer,
                    vk::PipelineStageFlags::HOST,
                    vk::PipelineStageFlags::TRANSFER,
                    vk::DependencyFlags::empty(),
                    &[],
                    &[],
                    slice::from_ref(&transfer_from_undef),
                )
            };

            let buffer_image_copy = vk::BufferImageCopy::builder()
                .image_subresource(
                    vk::ImageSubresourceLayers::builder()
                        .aspect_mask(vk::ImageAspectFlags::COLOR)
                        .layer_count(1)
                        .build(),
                )
                .image_extent(vk::Extent3D {
                    width: self.image_width,
                    height: self.image_height,
                    depth: 1,
                });

            unsafe {
                command_buffer.command_pool.device.cmd_copy_buffer_to_image(
                    ***command_buffer,
                    ***self.image_buffer.borrow(),
                    ***self.image.borrow(),
                    vk::ImageLayout::TRANSFER_DST_OPTIMAL,
                    slice::from_ref(&buffer_image_copy),
                )
            };

            let shader_from_transfer = vk::ImageMemoryBarrier::builder()
                .src_access_mask(vk::AccessFlags::TRANSFER_WRITE)
                .dst_access_mask(vk::AccessFlags::SHADER_READ)
                .old_layout(vk::ImageLayout::TRANSFER_DST_OPTIMAL)
                .new_layout(vk::ImageLayout::SHADER_READ_ONLY_OPTIMAL)
                .src_queue_family_index(vk::QUEUE_FAMILY_IGNORED)
                .dst_queue_family_index(vk::QUEUE_FAMILY_IGNORED)
                .image(***self.image.borrow())
                .subresource_range(
                    vk::ImageSubresourceRange::builder()
                        .aspect_mask(vk::ImageAspectFlags::COLOR)
                        .level_count(1)
                        .layer_count(1)
                        .build(),
                );
            unsafe {
                command_buffer.command_pool.device.cmd_pipeline_barrier(
                    ***command_buffer,
                    vk::PipelineStageFlags::TRANSFER,
                    vk::PipelineStageFlags::FRAGMENT_SHADER,
                    vk::DependencyFlags::empty(),
                    &[],
                    &[],
                    slice::from_ref(&shader_from_transfer),
                )
            };

            self.image_is_valid.set(true);
        }

        if self.old_pipeline.borrow().is_some() {
            self.old_pipeline.replace(None);
        }
    }

    pub fn set_renderpass(&self, render_pass: &RenderPass) {
        use crate::ash::{version::DeviceV1_0, vk};
        let device = &render_pass.device;
        self.render_pass.replace(Some(render_pass.clone()));
        let shader_entry_name = CStr::from_bytes_with_nul(b"main\0").unwrap();
        let shader_stage_create_info = [
            vk::PipelineShaderStageCreateInfo::builder()
                .stage(vk::ShaderStageFlags::VERTEX)
                .module(**self.vertex_shader)
                .name(&shader_entry_name)
                .build(),
            vk::PipelineShaderStageCreateInfo::builder()
                .stage(vk::ShaderStageFlags::FRAGMENT)
                .module(**self.fragment_shader)
                .name(&shader_entry_name)
                .build(),
        ];

        let vertex_input_binding = vk::VertexInputBindingDescription::builder()
            .binding(0)
            .stride(mem::size_of::<ImDrawVert>() as u32)
            .input_rate(vk::VertexInputRate::VERTEX);
        let vertex_input_attributes = [
            vk::VertexInputAttributeDescription::builder()
                .location(0)
                .binding(0)
                .format(vk::Format::R32G32_SFLOAT)
                .offset(offset_of!(ImDrawVert, pos) as u32)
                .build(),
            vk::VertexInputAttributeDescription::builder()
                .location(1)
                .binding(0)
                .format(vk::Format::R32G32_SFLOAT)
                .offset(offset_of!(ImDrawVert, uv) as u32)
                .build(),
            vk::VertexInputAttributeDescription::builder()
                .location(2)
                .binding(0)
                .format(vk::Format::R8G8B8A8_UNORM)
                .offset(offset_of!(ImDrawVert, col) as u32)
                .build(),
        ];

        let vertex_input_state_create_info = vk::PipelineVertexInputStateCreateInfo::builder()
            .vertex_binding_descriptions(slice::from_ref(&vertex_input_binding))
            .vertex_attribute_descriptions(&vertex_input_attributes);

        let input_assembly_state_create_info = vk::PipelineInputAssemblyStateCreateInfo::builder()
            .topology(vk::PrimitiveTopology::TRIANGLE_LIST);

        let viewport_state_create_info = vk::PipelineViewportStateCreateInfo::builder()
            .viewport_count(1)
            .scissor_count(1);

        let rasterization_state_create_info = vk::PipelineRasterizationStateCreateInfo::builder()
            .polygon_mode(vk::PolygonMode::FILL)
            .cull_mode(vk::CullModeFlags::NONE)
            .front_face(vk::FrontFace::CLOCKWISE)
            .line_width(1.0);

        let multisample_state_create_info = vk::PipelineMultisampleStateCreateInfo::builder()
            .rasterization_samples(vk::SampleCountFlags::TYPE_1);
        let color_blend_attachment_state = vk::PipelineColorBlendAttachmentState {
            blend_enable: vk::TRUE,
            src_color_blend_factor: vk::BlendFactor::SRC_ALPHA,
            dst_color_blend_factor: vk::BlendFactor::ONE_MINUS_SRC_ALPHA,
            color_blend_op: vk::BlendOp::ADD,
            src_alpha_blend_factor: vk::BlendFactor::ONE_MINUS_SRC_ALPHA,
            dst_alpha_blend_factor: vk::BlendFactor::ZERO,
            alpha_blend_op: vk::BlendOp::ADD,
            color_write_mask: vk::ColorComponentFlags::all(),
        };
        let color_blend_state_create_info = vk::PipelineColorBlendStateCreateInfo::builder()
            .attachments(slice::from_ref(&color_blend_attachment_state));

        let dynamic_states = [vk::DynamicState::VIEWPORT, vk::DynamicState::SCISSOR];
        let pipeline_dynamic_state_create_info =
            vk::PipelineDynamicStateCreateInfo::builder().dynamic_states(&dynamic_states);

        let pipeline_create_info = vk::GraphicsPipelineCreateInfo::builder()
            .stages(&shader_stage_create_info)
            .vertex_input_state(&vertex_input_state_create_info)
            .input_assembly_state(&input_assembly_state_create_info)
            .viewport_state(&viewport_state_create_info)
            .rasterization_state(&rasterization_state_create_info)
            .multisample_state(&multisample_state_create_info)
            .color_blend_state(&color_blend_state_create_info)
            .dynamic_state(&pipeline_dynamic_state_create_info)
            .layout(**self.pipeline_layout)
            .render_pass(***render_pass);

        self.old_pipeline.replace(Some(
            unsafe {
                device.create_graphics_pipelines(
                    vk::PipelineCache::null(),
                    slice::from_ref(&pipeline_create_info),
                    None,
                )
            }
            .unwrap()[0],
        ));
        self.old_pipeline.swap(&self.pipeline);
    }

    pub fn render(&self, ui: Ui, command_buffer: &CommandBuffer) -> Result<(), ()> {
        if self.render_pass.borrow().is_none() {
            return Err(());
        };

        let FrameSize {
            logical_size: (width, height),
            ..
        } = ui.frame_size();
        let width = width as f32;
        let height = height as f32;

        ui.render(|ui, mut draw_data| -> Result<_, u32> {
            use crate::ash::{version::DeviceV1_0, vk};
            draw_data.scale_clip_rects(ui.imgui().display_framebuffer_scale());

            let vertex_buffer = &self.vertex_buffers[*self.frame_index.borrow()];
            let index_buffer = &self.index_buffers[*self.frame_index.borrow()];

            unsafe {
                command_buffer.command_pool.device.cmd_bind_pipeline(
                    ***command_buffer,
                    vk::PipelineBindPoint::GRAPHICS,
                    *self.pipeline.borrow().as_ref().unwrap(),
                );
                command_buffer.command_pool.device.cmd_bind_descriptor_sets(
                    ***command_buffer,
                    vk::PipelineBindPoint::GRAPHICS,
                    **self.pipeline_layout,
                    0,
                    slice::from_ref(&self.descriptor_set),
                    &[],
                );
            }

            let dims_rcp = [1.0 / width, 1.0 / height];
            unsafe {
                command_buffer.command_pool.device.cmd_push_constants(
                    ***command_buffer,
                    **self.pipeline_layout,
                    vk::ShaderStageFlags::VERTEX,
                    0,
                    std::slice::from_raw_parts(
                        dims_rcp.as_ptr() as *const u8,
                        dims_rcp.len() * std::mem::size_of::<f32>() / std::mem::size_of::<u8>(),
                    ),
                )
            };

            let viewport = vk::Viewport {
                width,
                height,
                max_depth: 1.0,
                ..Default::default()
            };
            unsafe {
                command_buffer.command_pool.device.cmd_set_viewport(
                    ***command_buffer,
                    0,
                    slice::from_ref(&viewport),
                )
            };

            unsafe {
                command_buffer.command_pool.device.cmd_bind_vertex_buffers(
                    ***command_buffer,
                    0,
                    slice::from_ref(&***vertex_buffer),
                    &[0],
                );
                command_buffer.command_pool.device.cmd_bind_index_buffer(
                    ***command_buffer,
                    ***index_buffer,
                    0,
                    vk::IndexType::UINT16,
                );
            }

            let vertex_base = vertex_buffer.allocation_info.get_mapped_data() as *mut ImDrawVert;
            let index_base = index_buffer.allocation_info.get_mapped_data() as *mut ImDrawIdx;
            let mut vertex_offset = 0;
            let mut index_offset = 0;
            for draw_list in &draw_data {
                let next_vertex_offset = vertex_offset + draw_list.vtx_buffer.len();
                let next_index_offset = index_offset + draw_list.idx_buffer.len();
                if next_vertex_offset > Renderer::VERTEX_COUNT_PER_FRAME
                    || next_index_offset > Renderer::INDEX_COUNT_PER_FRAME
                {
                    break;
                }

                unsafe {
                    vertex_base
                        .add(vertex_offset)
                        .copy_from_nonoverlapping(draw_list.vtx_buffer.as_ptr(), draw_list.vtx_buffer.len());
                    index_base
                        .add(index_offset)
                        .copy_from_nonoverlapping(draw_list.idx_buffer.as_ptr(), draw_list.idx_buffer.len());
                }

                for cmd in draw_list.cmd_buffer {
                    let scissor = vk::Rect2D {
                        offset: vk::Offset2D {
                            x: cmd.clip_rect.x as i32,
                            y: cmd.clip_rect.y as i32,
                        },
                        extent: vk::Extent2D {
                            width: (cmd.clip_rect.z - cmd.clip_rect.x) as u32,
                            height: (cmd.clip_rect.w - cmd.clip_rect.y) as u32,
                        },
                    };
                    unsafe {
                        command_buffer.command_pool.device.cmd_set_scissor(
                            ***command_buffer,
                            0,
                            slice::from_ref(&scissor),
                        );
                        command_buffer.command_pool.device.cmd_draw_indexed(
                            ***command_buffer,
                            cmd.elem_count,
                            1,
                            index_offset as u32,
                            vertex_offset as i32,
                            0,
                        );
                    }

                    index_offset += cmd.elem_count as usize;
                }

                vertex_offset = next_vertex_offset;
                assert_eq!(index_offset, next_index_offset);
            }

            vertex_buffer.flush(0, 0).unwrap();
            index_buffer.flush(0, 0).unwrap();

            Ok(())
        })
        .unwrap();

        self.frame_index
            .replace_with(|frame_index| (1 + *frame_index) % Renderer::FRAME_COUNT);

        Ok(())
    }
}