WIP "Vertex buffers: Vertex input description"

TODO: "Vertex buffer creation"
https://vulkan-tutorial.com/Vertex_buffers/Vertex_buffer_creation

Note that triangle drawing doesn't work at this stage.
This commit is contained in:
Stephen Seo 2024-03-15 14:31:47 +09:00
parent fa26784e01
commit 07b384a6c7
3 changed files with 132 additions and 28 deletions

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@ -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);
fragColor = colors[gl_VertexIndex];
gl_Position = vec4(inPosition, 0.0, 1.0);
fragColor = inColor;
}

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@ -1,8 +1,11 @@
mod ffi;
mod math3d;
use std::collections::HashSet;
use std::ffi::{c_void, CStr, CString};
use math3d::Vertex;
const WINDOW_WIDTH: i32 = 800;
const WINDOW_HEIGHT: i32 = 600;
@ -926,7 +929,19 @@ impl VulkanApp {
let shader_stages: [ffi::VkPipelineShaderStageCreateInfo; 2] =
[vert_shader_stage_info, frag_shader_stage_info];
let vertex_input_info = Self::create_vertex_input_state_info_struct();
let mut vertex_input_info: ffi::VkPipelineVertexInputStateCreateInfo =
unsafe { std::mem::zeroed() };
vertex_input_info.sType =
ffi::VkStructureType_VK_STRUCTURE_TYPE_PIPELINE_VERTEX_INPUT_STATE_CREATE_INFO;
let bind_desc = Vertex::get_binding_description();
let attr_descs = Vertex::get_attribute_descriptions();
vertex_input_info.vertexBindingDescriptionCount = 1;
vertex_input_info.vertexAttributeDescriptionCount = attr_descs.len() as u32;
vertex_input_info.pVertexBindingDescriptions = std::ptr::addr_of!(bind_desc);
vertex_input_info.pVertexAttributeDescriptions = attr_descs.as_ptr();
let mut input_assembly: ffi::VkPipelineInputAssemblyStateCreateInfo =
unsafe { std::mem::zeroed() };
@ -1074,19 +1089,6 @@ impl VulkanApp {
dynamic_state
}
fn create_vertex_input_state_info_struct() -> ffi::VkPipelineVertexInputStateCreateInfo {
let mut vertex_input_info: ffi::VkPipelineVertexInputStateCreateInfo =
unsafe { std::mem::zeroed() };
vertex_input_info.sType =
ffi::VkStructureType_VK_STRUCTURE_TYPE_PIPELINE_VERTEX_INPUT_STATE_CREATE_INFO;
vertex_input_info.vertexBindingDescriptionCount = 0;
vertex_input_info.pVertexBindingDescriptions = std::ptr::null();
vertex_input_info.vertexAttributeDescriptionCount = 0;
vertex_input_info.pVertexBindingDescriptions = std::ptr::null();
vertex_input_info
}
fn create_viewport(&self) -> ffi::VkViewport {
let mut viewport: ffi::VkViewport = unsafe { std::mem::zeroed() };
viewport.x = 0.0;

111
src/math3d.rs Normal file
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@ -0,0 +1,111 @@
use crate::ffi;
#[repr(C)]
#[derive(Copy, Clone, PartialEq, Debug)]
pub struct Vertex {
pos: [f32; 2],
color: [f32; 3],
}
impl Default for Vertex {
fn default() -> Self {
Self {
pos: [0.0, 0.0],
color: [0.0, 0.0, 0.0],
}
}
}
impl Vertex {
pub fn pos_offset() -> usize {
0
}
pub fn color_offset() -> usize {
let mut offset = std::mem::size_of::<[f32; 2]>();
let alignment = std::mem::align_of::<[f32; 3]>();
while offset % alignment != 0 {
offset += 1;
}
offset
}
pub fn get_binding_description() -> ffi::VkVertexInputBindingDescription {
let mut bind_desc: ffi::VkVertexInputBindingDescription = unsafe { std::mem::zeroed() };
bind_desc.binding = 0;
bind_desc.stride = std::mem::size_of::<Self>() as u32;
bind_desc.inputRate = ffi::VkVertexInputRate_VK_VERTEX_INPUT_RATE_VERTEX;
bind_desc
}
pub fn get_attribute_descriptions() -> [ffi::VkVertexInputAttributeDescription; 2] {
let mut attr_descs: [ffi::VkVertexInputAttributeDescription; 2] =
unsafe { std::mem::zeroed() };
attr_descs[0].binding = 0;
attr_descs[0].location = 0;
attr_descs[0].format = ffi::VkFormat_VK_FORMAT_R32G32_SFLOAT;
attr_descs[0].offset = Self::pos_offset() as u32;
attr_descs[1].binding = 0;
attr_descs[1].location = 1;
attr_descs[1].format = ffi::VkFormat_VK_FORMAT_R32G32B32_SFLOAT;
attr_descs[1].offset = Self::color_offset() as u32;
attr_descs
}
}
#[cfg(test)]
mod tests {
use super::*;
#[test]
fn offsets() {
let mut vertex = Vertex {
pos: [1.0, 2.0],
color: [3.0, 4.0, 5.0],
};
let root_ptr: *const f32 = &vertex as *const Vertex as *const f32;
let pos_offset = Vertex::pos_offset();
assert!(pos_offset + 4 <= std::mem::size_of::<Vertex>());
let pos_0_ptr = unsafe { root_ptr.byte_add(pos_offset) };
assert_eq!(unsafe { *pos_0_ptr }, vertex.pos[0]);
assert!(pos_offset + 8 <= std::mem::size_of::<Vertex>());
let pos_1_ptr = unsafe { root_ptr.byte_add(pos_offset + 4) };
assert_eq!(unsafe { *pos_1_ptr }, vertex.pos[1]);
let color_offset = Vertex::color_offset();
assert!(color_offset + 4 <= std::mem::size_of::<Vertex>());
let col_0_ptr = unsafe { root_ptr.byte_add(color_offset) };
assert_eq!(unsafe { *col_0_ptr }, vertex.color[0]);
assert!(color_offset + 8 <= std::mem::size_of::<Vertex>());
let col_1_ptr = unsafe { root_ptr.byte_add(color_offset + 4) };
assert_eq!(unsafe { *col_1_ptr }, vertex.color[1]);
assert!(color_offset + 12 <= std::mem::size_of::<Vertex>());
let col_2_ptr = unsafe { root_ptr.byte_add(color_offset + 8) };
assert_eq!(unsafe { *col_2_ptr }, vertex.color[2]);
vertex.pos[0] = 0.123;
vertex.pos[1] = 0.456;
vertex.color[0] = 0.789;
vertex.color[1] = 1.234;
vertex.color[2] = 1.567;
assert_eq!(unsafe { *pos_0_ptr }, vertex.pos[0]);
assert_eq!(unsafe { *pos_1_ptr }, vertex.pos[1]);
assert_eq!(unsafe { *col_0_ptr }, vertex.color[0]);
assert_eq!(unsafe { *col_1_ptr }, vertex.color[1]);
assert_eq!(unsafe { *col_2_ptr }, vertex.color[2]);
}
}