Move shader vertices into a vertex buffer

shaders/shader.vert

@@ -1,20 +1,11 @@
 #version 450
 
+layout(location = 0) in vec2 inPosition;
+layout(location = 1) in vec3 inColor;
+
 layout(location = 0) out vec3 fragColor;
 
-vec2 positions[3] = vec2[](
-    vec2(0.0, -0.5),
-    vec2(0.5, 0.5),
-    vec2(-0.5, 0.5)
-);
-
-vec3 colors[3] = vec3[](
-    vec3(1.0, 0.0, 0.0),
-    vec3(0.0, 1.0, 0.0),
-    vec3(0.0, 0.0, 1.0)
-);
-
 void main() {
-    gl_Position = vec4(positions[gl_VertexIndex], 0.0, 1.0);
+    gl_Position = vec4(inPosition, 0.0, 1.0);
-    fragColor = colors[gl_VertexIndex];
+    fragColor = inColor;
 }

src/app.rs

@@ -2,12 +2,15 @@ mod functions;
 use functions::{
     create_command_buffers, create_command_pool, create_framebuffers, create_instance,
     create_logical_device, create_pipeline, create_render_pass, create_swapchain,
-    create_swapchain_image_views, create_sync_objects, pick_physical_device,
+    create_swapchain_image_views, create_sync_objects, create_vertex_buffer, pick_physical_device,
 };
 
 use crate::VALIDATION_ENABLED;
 use ::anyhow::{anyhow, Result};
+use ::lazy_static::lazy_static;
 use ::log::*;
+use ::nalgebra_glm as glm;
+use ::std::mem::size_of;
 use ::thiserror::Error;
 use ::vulkanalia::loader::{LibloadingLoader, LIBRARY};
 use ::vulkanalia::prelude::v1_0::*;
@@ -63,6 +66,7 @@ impl App {
         create_pipeline(&device, &mut data)?;
         create_framebuffers(&device, &mut data)?;
         create_command_pool(&instance, &device, &mut data)?;
+        create_vertex_buffer(&instance, &device, &mut data)?;
         create_command_buffers(&device, &mut data)?;
         create_sync_objects(&device, &mut data)?;
 
@@ -82,6 +86,9 @@ impl App {
     /// Here be Dragons
     pub unsafe fn destroy(&mut self) {
         self.destroy_swapchain();
+        self.device.destroy_buffer(self.data.vertex_buffer, None);
+        self.device
+            .free_memory(self.data.vertex_buffer_memory, None);
 
         self.data
             .in_flight_fences
@@ -248,6 +255,9 @@ pub struct AppData {
     framebuffers: Vec<vk::Framebuffer>,
     // Command Pool
     command_pool: vk::CommandPool,
+    // Buffers
+    vertex_buffer: vk::Buffer,
+    vertex_buffer_memory: vk::DeviceMemory,
     // Command Buffers
     command_buffers: Vec<vk::CommandBuffer>,
     // Sync Objects
@@ -327,3 +337,50 @@ impl SwapchainSupport {
         })
     }
 }
+
+#[repr(C)]
+#[derive(Copy, Clone, Debug)]
+pub(crate) struct Vertex {
+    pos: glm::Vec2,
+    color: glm::Vec3,
+}
+
+impl Vertex {
+    fn new(pos: glm::Vec2, color: glm::Vec3) -> Self {
+        Self { pos, color }
+    }
+
+    pub fn binding_description() -> vk::VertexInputBindingDescription {
+        vk::VertexInputBindingDescription::builder()
+            .binding(0)
+            .stride(size_of::<Vertex>() as u32)
+            .input_rate(vk::VertexInputRate::VERTEX)
+            .build()
+    }
+
+    pub fn attribute_descriptions() -> [vk::VertexInputAttributeDescription; 2] {
+        let pos = vk::VertexInputAttributeDescription::builder()
+            .binding(0)
+            .location(0)
+            .format(vk::Format::R32G32_SFLOAT)
+            .offset(0)
+            .build();
+
+        let color = vk::VertexInputAttributeDescription::builder()
+            .binding(0)
+            .location(1)
+            .format(vk::Format::R32G32B32_SFLOAT)
+            .offset(size_of::<glm::Vec2>() as u32)
+            .build();
+
+        [pos, color]
+    }
+}
+
+lazy_static! {
+    pub(crate) static ref VERTICES: Vec<Vertex> = vec![
+        Vertex::new(glm::vec2(0.0, -0.5), glm::vec3(1.0, 0.0, 0.0)),
+        Vertex::new(glm::vec2(0.5, 0.5), glm::vec3(0.0, 1.0, 0.0)),
+        Vertex::new(glm::vec2(-0.5, 0.5), glm::vec3(0.0, 0.0, 1.0)),
+    ];
+}

src/app/functions.rs

@@ -6,6 +6,7 @@ use ::log::*;
 use ::std::collections::HashSet;
 use ::std::ffi::CStr;
 use ::std::os::raw::c_void;
+use ::std::ptr::copy_nonoverlapping as memcpy;
 use ::vulkanalia::prelude::v1_0::*;
 use ::vulkanalia::window as vk_window;
 use ::winit::window::Window;
@@ -437,7 +438,11 @@ pub(super) unsafe fn create_pipeline(device: &Device, data: &mut AppData) -> Res
         .module(frag_shader_module)
         .name(b"main\0");
 
-    let vertex_input_state = vk::PipelineVertexInputStateCreateInfo::builder();
+    let binding_descriptions = &[Vertex::binding_description()];
+    let attribute_descriptions = Vertex::attribute_descriptions();
+    let vertex_input_state = vk::PipelineVertexInputStateCreateInfo::builder()
+        .vertex_binding_descriptions(binding_descriptions)
+        .vertex_attribute_descriptions(&attribute_descriptions);
 
     let input_assembly_state = vk::PipelineInputAssemblyStateCreateInfo::builder()
         .topology(vk::PrimitiveTopology::TRIANGLE_LIST)
@@ -618,6 +623,7 @@ pub(super) unsafe fn create_command_buffers(device: &Device, data: &mut AppData)
             vk::PipelineBindPoint::GRAPHICS,
             data.pipeline,
         );
+        device.cmd_bind_vertex_buffers(*command_buffer, 0, &[data.vertex_buffer], &[0]);
         device.cmd_draw(*command_buffer, 3, 1, 0, 0);
         device.cmd_end_render_pass(*command_buffer);
 
@@ -649,3 +655,59 @@ pub(super) unsafe fn create_sync_objects(device: &Device, data: &mut AppData) ->
 
     Ok(())
 }
+
+pub(super) unsafe fn create_vertex_buffer(
+    instance: &Instance,
+    device: &Device,
+    data: &mut AppData,
+) -> Result<()> {
+    let buffer_info = vk::BufferCreateInfo::builder()
+        .size((size_of::<Vertex>() * VERTICES.len()) as u64)
+        .usage(vk::BufferUsageFlags::VERTEX_BUFFER)
+        .sharing_mode(vk::SharingMode::EXCLUSIVE);
+
+    data.vertex_buffer = device.create_buffer(&buffer_info, None)?;
+
+    let requirements = device.get_buffer_memory_requirements(data.vertex_buffer);
+    let memory_info = vk::MemoryAllocateInfo::builder()
+        .allocation_size(requirements.size)
+        .memory_type_index(get_memory_type_index(
+            instance,
+            data,
+            vk::MemoryPropertyFlags::HOST_COHERENT | vk::MemoryPropertyFlags::HOST_VISIBLE,
+            requirements,
+        )?);
+
+    data.vertex_buffer_memory = device.allocate_memory(&memory_info, None)?;
+
+    device.bind_buffer_memory(data.vertex_buffer, data.vertex_buffer_memory, 0)?;
+
+    let memory = device.map_memory(
+        data.vertex_buffer_memory,
+        0,
+        buffer_info.size,
+        vk::MemoryMapFlags::empty(),
+    )?;
+
+    memcpy(VERTICES.as_ptr(), memory.cast(), VERTICES.len());
+    device.unmap_memory(data.vertex_buffer_memory);
+
+    Ok(())
+}
+
+unsafe fn get_memory_type_index(
+    instance: &Instance,
+    data: &AppData,
+    properties: vk::MemoryPropertyFlags,
+    requirements: vk::MemoryRequirements,
+) -> Result<u32> {
+    let memory = instance.get_physical_device_memory_properties(data.physical_device);
+
+    (0..memory.memory_type_count)
+        .find(|i| {
+            let suitable = (requirements.memory_type_bits & (1 << i)) != 0;
+            let memory_type = memory.memory_types[*i as usize];
+            suitable && memory_type.property_flags.contains(properties)
+        })
+        .ok_or_else(|| anyhow!("Failed to find suitable memory type."))
+}