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Merge #19

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This commit is contained in:
Andrew Wheeler(Genusis) 2022-10-06 12:13:43 -04:00 committed by Josh Groves
parent afab881559
commit 4075536745
4 changed files with 678 additions and 659 deletions
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37
src/error.rs Normal file
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@ -0,0 +1,37 @@
use std::{
error::Error,
fmt::{self, Display, Formatter},
};
#[derive(Clone, Copy, Debug, Eq, PartialEq)]
pub enum PrepareError {
AtlasFull,
}
impl Display for PrepareError {
fn fmt(&self, f: &mut Formatter) -> fmt::Result {
write!(f, "Prepare Error: The Glyph texture atlas is full.")
}
}
impl Error for PrepareError {}
#[derive(Clone, Copy, Debug, Eq, PartialEq)]
pub enum RenderError {
RemovedFromAtlas,
ScreenResolutionChanged,
}
impl Display for RenderError {
fn fmt(&self, f: &mut Formatter) -> fmt::Result {
match self {
RenderError::RemovedFromAtlas => {
write!(f, "Render Error: Glyph no longer Exists within the Atlas.")
}
RenderError::ScreenResolutionChanged => write!(
f,
"Render Error: Screen resolution changed since prepare was last executed."
),
}
}
}

672
src/lib.rs
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@ -1,35 +1,15 @@
use std::{ use etagere::AllocId;
borrow::Cow,
collections::HashSet,
error::Error,
fmt::{self, Display, Formatter},
iter,
mem::size_of,
num::{NonZeroU32, NonZeroU64},
slice,
sync::Arc,
};
use etagere::{size2, AllocId, Allocation, BucketedAtlasAllocator};
use fontdue::{
layout::{GlyphRasterConfig, Layout},
Font,
};
use recently_used::RecentlyUsedMap;
use wgpu::{
BindGroup, BindGroupEntry, BindGroupLayoutEntry, BindingResource, BindingType, BlendState,
Buffer, BufferBindingType, BufferDescriptor, BufferUsages, ColorTargetState, ColorWrites,
Device, Extent3d, FilterMode, FragmentState, ImageCopyTexture, ImageDataLayout, IndexFormat,
MultisampleState, Origin3d, PipelineLayoutDescriptor, PrimitiveState, Queue, RenderPass,
RenderPipeline, RenderPipelineDescriptor, SamplerBindingType, SamplerDescriptor,
ShaderModuleDescriptor, ShaderSource, ShaderStages, Texture, TextureAspect, TextureDescriptor,
TextureDimension, TextureFormat, TextureSampleType, TextureUsages, TextureViewDescriptor,
TextureViewDimension, VertexFormat, VertexState, COPY_BUFFER_ALIGNMENT,
};
pub use fontdue;
mod error;
mod recently_used; mod recently_used;
mod text_atlas;
mod text_render;
pub use error::{PrepareError, RenderError};
pub use fontdue;
use recently_used::RecentlyUsedMap;
pub use text_atlas::TextAtlas;
pub use text_render::TextRenderer;
#[repr(C)] #[repr(C)]
pub struct Color { pub struct Color {
@ -43,37 +23,12 @@ pub trait HasColor: Copy {
fn color(&self) -> Color; fn color(&self) -> Color;
} }
#[derive(Clone, Copy, Debug, Eq, PartialEq)] pub(crate) enum GpuCache {
pub enum PrepareError {
AtlasFull,
}
impl Display for PrepareError {
fn fmt(&self, f: &mut Formatter) -> fmt::Result {
write!(f, "prepare error")
}
}
impl Error for PrepareError {}
#[derive(Clone, Copy, Debug, Eq, PartialEq)]
pub enum RenderError {
RemovedFromAtlas,
ScreenResolutionChanged,
}
impl Display for RenderError {
fn fmt(&self, f: &mut Formatter) -> fmt::Result {
write!(f, "render error")
}
}
enum GpuCache {
InAtlas { x: u16, y: u16 }, InAtlas { x: u16, y: u16 },
SkipRasterization, SkipRasterization,
} }
struct GlyphDetails { pub(crate) struct GlyphDetails {
width: u16, width: u16,
height: u16, height: u16,
gpu_cache: GpuCache, gpu_cache: GpuCache,
@ -82,7 +37,7 @@ struct GlyphDetails {
#[repr(C)] #[repr(C)]
#[derive(Clone, Copy, Debug)] #[derive(Clone, Copy, Debug)]
struct GlyphToRender { pub(crate) struct GlyphToRender {
pos: [u32; 2], pos: [u32; 2],
dim: [u16; 2], dim: [u16; 2],
uv: [u16; 2], uv: [u16; 2],
@ -103,219 +58,6 @@ pub struct Params {
_pad: [u32; 2], _pad: [u32; 2],
} }
fn try_allocate(atlas: &mut TextAtlas, width: usize, height: usize) -> Option<Allocation> {
let size = size2(width as i32, height as i32);
loop {
let allocation = atlas.packer.allocate(size);
if allocation.is_some() {
return allocation;
}
// Try to free least recently used allocation
let (key, value) = atlas.glyph_cache.pop()?;
atlas
.packer
.deallocate(value.atlas_id.expect("cache corrupt"));
atlas.glyph_cache.remove(&key);
}
}
pub struct TextAtlas {
texture_pending: Vec<u8>,
texture: Texture,
packer: BucketedAtlasAllocator,
width: u32,
height: u32,
glyph_cache: RecentlyUsedMap<GlyphRasterConfig, GlyphDetails>,
params: Params,
params_buffer: Buffer,
pipeline: Arc<RenderPipeline>,
bind_group: Arc<BindGroup>,
}
impl TextAtlas {
pub fn new(device: &Device, _queue: &Queue, format: TextureFormat) -> Self {
let max_texture_dimension_2d = device.limits().max_texture_dimension_2d;
let width = max_texture_dimension_2d;
let height = max_texture_dimension_2d;
let packer = BucketedAtlasAllocator::new(size2(width as i32, height as i32));
// Create a texture to use for our atlas
let texture_pending = vec![0; (width * height) as usize];
let texture = device.create_texture(&TextureDescriptor {
label: Some("glyphon atlas"),
size: Extent3d {
width,
height,
depth_or_array_layers: 1,
},
mip_level_count: 1,
sample_count: 1,
dimension: TextureDimension::D2,
format: TextureFormat::R8Unorm,
usage: TextureUsages::TEXTURE_BINDING | TextureUsages::COPY_DST,
});
let texture_view = texture.create_view(&TextureViewDescriptor::default());
let sampler = device.create_sampler(&SamplerDescriptor {
label: Some("glyphon sampler"),
min_filter: FilterMode::Nearest,
mag_filter: FilterMode::Nearest,
mipmap_filter: FilterMode::Nearest,
lod_min_clamp: 0f32,
lod_max_clamp: 0f32,
..Default::default()
});
let glyph_cache = RecentlyUsedMap::new();
// Create a render pipeline to use for rendering later
let shader = device.create_shader_module(ShaderModuleDescriptor {
label: Some("glyphon shader"),
source: ShaderSource::Wgsl(Cow::Borrowed(include_str!("shader.wgsl"))),
});
let vertex_buffers = [wgpu::VertexBufferLayout {
array_stride: size_of::<GlyphToRender>() as wgpu::BufferAddress,
step_mode: wgpu::VertexStepMode::Vertex,
attributes: &[
wgpu::VertexAttribute {
format: VertexFormat::Uint32x2,
offset: 0,
shader_location: 0,
},
wgpu::VertexAttribute {
format: VertexFormat::Uint32,
offset: size_of::<u32>() as u64 * 2,
shader_location: 1,
},
wgpu::VertexAttribute {
format: VertexFormat::Uint32,
offset: size_of::<u32>() as u64 * 3,
shader_location: 2,
},
wgpu::VertexAttribute {
format: VertexFormat::Uint32,
offset: size_of::<u32>() as u64 * 4,
shader_location: 3,
},
],
}];
let bind_group_layout = device.create_bind_group_layout(&wgpu::BindGroupLayoutDescriptor {
entries: &[
BindGroupLayoutEntry {
binding: 0,
visibility: ShaderStages::VERTEX,
ty: BindingType::Buffer {
ty: BufferBindingType::Uniform,
has_dynamic_offset: false,
min_binding_size: NonZeroU64::new(size_of::<Params>() as u64),
},
count: None,
},
BindGroupLayoutEntry {
binding: 1,
visibility: ShaderStages::VERTEX | ShaderStages::FRAGMENT,
ty: BindingType::Texture {
multisampled: false,
view_dimension: TextureViewDimension::D2,
sample_type: TextureSampleType::Float { filterable: true },
},
count: None,
},
BindGroupLayoutEntry {
binding: 2,
visibility: ShaderStages::FRAGMENT,
ty: BindingType::Sampler(SamplerBindingType::Filtering),
count: None,
},
],
label: Some("glyphon bind group layout"),
});
let params = Params {
screen_resolution: Resolution {
width: 0,
height: 0,
},
_pad: [0, 0],
};
let params_buffer = device.create_buffer(&BufferDescriptor {
label: Some("glyphon params"),
size: size_of::<Params>() as u64,
usage: BufferUsages::UNIFORM | BufferUsages::COPY_DST,
mapped_at_creation: false,
});
let bind_group = Arc::new(device.create_bind_group(&wgpu::BindGroupDescriptor {
layout: &bind_group_layout,
entries: &[
BindGroupEntry {
binding: 0,
resource: params_buffer.as_entire_binding(),
},
BindGroupEntry {
binding: 1,
resource: BindingResource::TextureView(&texture_view),
},
BindGroupEntry {
binding: 2,
resource: BindingResource::Sampler(&sampler),
},
],
label: Some("glyphon bind group"),
}));
let pipeline_layout = device.create_pipeline_layout(&PipelineLayoutDescriptor {
label: None,
bind_group_layouts: &[&bind_group_layout],
push_constant_ranges: &[],
});
let pipeline = Arc::new(device.create_render_pipeline(&RenderPipelineDescriptor {
label: Some("glyphon pipeline"),
layout: Some(&pipeline_layout),
vertex: VertexState {
module: &shader,
entry_point: "vs_main",
buffers: &vertex_buffers,
},
fragment: Some(FragmentState {
module: &shader,
entry_point: "fs_main",
targets: &[Some(ColorTargetState {
format,
blend: Some(BlendState::PREMULTIPLIED_ALPHA_BLENDING),
write_mask: ColorWrites::default(),
})],
}),
primitive: PrimitiveState::default(),
depth_stencil: None,
multisample: MultisampleState {
count: 1,
mask: !0,
alpha_to_coverage_enabled: false,
},
multiview: None,
}));
Self {
texture_pending,
texture,
packer,
width,
height,
glyph_cache,
params,
params_buffer,
pipeline,
bind_group,
}
}
}
/// Controls the overflow behavior of any glyphs that are outside of the layout bounds. /// Controls the overflow behavior of any glyphs that are outside of the layout bounds.
pub enum TextOverflow { pub enum TextOverflow {
/// Glyphs can overflow the bounds. /// Glyphs can overflow the bounds.
@ -324,391 +66,3 @@ pub enum TextOverflow {
/// clipped to the bounds. /// clipped to the bounds.
Hide, Hide,
} }
pub struct TextRenderer {
vertex_buffer: Buffer,
vertex_buffer_size: u64,
index_buffer: Buffer,
index_buffer_size: u64,
vertices_to_render: u32,
glyphs_in_use: HashSet<GlyphRasterConfig>,
screen_resolution: Resolution,
}
impl TextRenderer {
pub fn new(device: &Device, _queue: &Queue) -> Self {
let vertex_buffer_size = next_copy_buffer_size(4096);
let vertex_buffer = device.create_buffer(&BufferDescriptor {
label: Some("glyphon vertices"),
size: vertex_buffer_size,
usage: BufferUsages::VERTEX | BufferUsages::COPY_DST,
mapped_at_creation: false,
});
let index_buffer_size = next_copy_buffer_size(4096);
let index_buffer = device.create_buffer(&BufferDescriptor {
label: Some("glyphon indices"),
size: index_buffer_size,
usage: BufferUsages::INDEX | BufferUsages::COPY_DST,
mapped_at_creation: false,
});
Self {
vertex_buffer,
vertex_buffer_size,
index_buffer,
index_buffer_size,
vertices_to_render: 0,
glyphs_in_use: HashSet::new(),
screen_resolution: Resolution {
width: 0,
height: 0,
},
}
}
pub fn prepare(
&mut self,
device: &Device,
queue: &Queue,
atlas: &mut TextAtlas,
screen_resolution: Resolution,
fonts: &[Font],
layouts: &[(Layout<impl HasColor>, TextOverflow)],
) -> Result<(), PrepareError> {
self.screen_resolution = screen_resolution;
let atlas_current_resolution = { atlas.params.screen_resolution };
if screen_resolution != atlas_current_resolution {
atlas.params.screen_resolution = screen_resolution;
queue.write_buffer(&atlas.params_buffer, 0, unsafe {
slice::from_raw_parts(
&atlas.params as *const Params as *const u8,
size_of::<Params>(),
)
});
}
struct UploadBounds {
x_min: usize,
x_max: usize,
y_min: usize,
y_max: usize,
}
let mut upload_bounds = None::<UploadBounds>;
self.glyphs_in_use.clear();
for (layout, _) in layouts.iter() {
for glyph in layout.glyphs() {
self.glyphs_in_use.insert(glyph.key);
let already_on_gpu = atlas.glyph_cache.contains_key(&glyph.key);
if already_on_gpu {
continue;
}
let font = &fonts[glyph.font_index];
let (metrics, bitmap) = font.rasterize_config(glyph.key);
let (gpu_cache, atlas_id) = if glyph.char_data.rasterize() {
// Find a position in the packer
let allocation = match try_allocate(atlas, metrics.width, metrics.height) {
Some(a) => a,
None => return Err(PrepareError::AtlasFull),
};
let atlas_min = allocation.rectangle.min;
let atlas_max = allocation.rectangle.max;
for row in 0..metrics.height {
let y_offset = atlas_min.y as usize;
let x_offset =
(y_offset + row) * atlas.width as usize + atlas_min.x as usize;
let bitmap_row = &bitmap[row * metrics.width..(row + 1) * metrics.width];
atlas.texture_pending[x_offset..x_offset + metrics.width]
.copy_from_slice(bitmap_row);
}
match upload_bounds.as_mut() {
Some(ub) => {
ub.x_min = ub.x_min.min(atlas_min.x as usize);
ub.x_max = ub.x_max.max(atlas_max.x as usize);
ub.y_min = ub.y_min.min(atlas_min.y as usize);
ub.y_max = ub.y_max.max(atlas_max.y as usize);
}
None => {
upload_bounds = Some(UploadBounds {
x_min: atlas_min.x as usize,
x_max: atlas_max.x as usize,
y_min: atlas_min.y as usize,
y_max: atlas_max.y as usize,
});
}
}
(
GpuCache::InAtlas {
x: atlas_min.x as u16,
y: atlas_min.y as u16,
},
Some(allocation.id),
)
} else {
(GpuCache::SkipRasterization, None)
};
if !atlas.glyph_cache.contains_key(&glyph.key) {
atlas.glyph_cache.insert(
glyph.key,
GlyphDetails {
width: metrics.width as u16,
height: metrics.height as u16,
gpu_cache,
atlas_id,
},
);
}
}
}
if let Some(ub) = upload_bounds {
queue.write_texture(
ImageCopyTexture {
texture: &atlas.texture,
mip_level: 0,
origin: Origin3d {
x: ub.x_min as u32,
y: ub.y_min as u32,
z: 0,
},
aspect: TextureAspect::All,
},
&atlas.texture_pending[ub.y_min * atlas.width as usize + ub.x_min..],
ImageDataLayout {
offset: 0,
bytes_per_row: NonZeroU32::new(atlas.width as u32),
rows_per_image: NonZeroU32::new(atlas.height as u32),
},
Extent3d {
width: (ub.x_max - ub.x_min) as u32,
height: (ub.y_max - ub.y_min) as u32,
depth_or_array_layers: 1,
},
);
}
let mut glyph_vertices = Vec::new();
let mut glyph_indices = Vec::new();
let mut glyphs_added = 0;
for (layout, overflow) in layouts.iter() {
let settings = layout.settings();
// Note: subpixel positioning is not currently handled, so we always use the nearest
// pixel.
let bounds_min_x = settings.x.round() as u32;
let bounds_max_x = settings
.max_width
.map(|w| bounds_min_x + w.round() as u32)
.unwrap_or(u32::MAX);
let bounds_min_y = settings.y.round() as u32;
let bounds_max_y = settings
.max_height
.map(|h| bounds_min_y + h.round() as u32)
.unwrap_or(u32::MAX);
for glyph in layout.glyphs() {
let mut x = glyph.x.round() as u32;
let mut y = glyph.y.round() as u32;
let details = atlas.glyph_cache.get(&glyph.key).unwrap();
let (mut atlas_x, mut atlas_y) = match details.gpu_cache {
GpuCache::InAtlas { x, y } => (x, y),
GpuCache::SkipRasterization => continue,
};
let mut width = details.width as u32;
let mut height = details.height as u32;
match overflow {
TextOverflow::Overflow => {}
TextOverflow::Hide => {
// Starts beyond right edge or ends beyond left edge
let max_x = x + width;
if x > bounds_max_x || max_x < bounds_min_x {
continue;
}
// Starts beyond bottom edge or ends beyond top edge
let max_y = y + height;
if y > bounds_max_y || max_y < bounds_min_y {
continue;
}
// Clip left ege
if x < bounds_min_x {
let right_shift = bounds_min_x - x;
x = bounds_min_x;
width = max_x - bounds_min_x;
atlas_x += right_shift as u16;
}
// Clip right edge
if x + width > bounds_max_x {
width = bounds_max_x - x;
}
// Clip top edge
if y < bounds_min_y {
let bottom_shift = bounds_min_y - y;
y = bounds_min_y;
height = max_y - bounds_min_y;
atlas_y += bottom_shift as u16;
}
// Clip bottom edge
if y + height > bounds_max_y {
height = bounds_max_y - y;
}
}
}
let color = glyph.user_data.color();
glyph_vertices.extend(
iter::repeat(GlyphToRender {
pos: [x, y],
dim: [width as u16, height as u16],
uv: [atlas_x, atlas_y],
color: [color.r, color.g, color.b, color.a],
})
.take(4),
);
let start = 4 * glyphs_added as u32;
glyph_indices.extend([start, start + 1, start + 2, start, start + 2, start + 3]);
glyphs_added += 1;
}
}
const VERTICES_PER_GLYPH: u32 = 6;
self.vertices_to_render = glyphs_added as u32 * VERTICES_PER_GLYPH;
let will_render = glyphs_added > 0;
if !will_render {
return Ok(());
}
let vertices = glyph_vertices.as_slice();
let vertices_raw = unsafe {
slice::from_raw_parts(
vertices as *const _ as *const u8,
size_of::<GlyphToRender>() * vertices.len(),
)
};
if self.vertex_buffer_size >= vertices_raw.len() as u64 {
queue.write_buffer(&self.vertex_buffer, 0, vertices_raw);
} else {
self.vertex_buffer.destroy();
let (buffer, buffer_size) = create_oversized_buffer(
device,
Some("glyphon vertices"),
vertices_raw,
BufferUsages::VERTEX | BufferUsages::COPY_DST,
);
self.vertex_buffer = buffer;
self.vertex_buffer_size = buffer_size;
}
let indices = glyph_indices.as_slice();
let indices_raw = unsafe {
slice::from_raw_parts(
indices as *const _ as *const u8,
size_of::<u32>() * indices.len(),
)
};
if self.index_buffer_size >= indices_raw.len() as u64 {
queue.write_buffer(&self.index_buffer, 0, indices_raw);
} else {
self.index_buffer.destroy();
let (buffer, buffer_size) = create_oversized_buffer(
device,
Some("glyphon indices"),
indices_raw,
BufferUsages::INDEX | BufferUsages::COPY_DST,
);
self.index_buffer = buffer;
self.index_buffer_size = buffer_size;
}
Ok(())
}
pub fn render<'pass>(
&'pass mut self,
atlas: &'pass TextAtlas,
pass: &mut RenderPass<'pass>,
) -> Result<(), RenderError> {
if self.vertices_to_render == 0 {
return Ok(());
}
{
// Validate that glyphs haven't been evicted from cache since `prepare`
for glyph in self.glyphs_in_use.iter() {
if !atlas.glyph_cache.contains_key(glyph) {
return Err(RenderError::RemovedFromAtlas);
}
}
// Validate that screen resolution hasn't changed since `prepare`
if self.screen_resolution != atlas.params.screen_resolution {
return Err(RenderError::ScreenResolutionChanged);
}
}
pass.set_pipeline(&atlas.pipeline);
pass.set_bind_group(0, &atlas.bind_group, &[]);
pass.set_vertex_buffer(0, self.vertex_buffer.slice(..));
pass.set_index_buffer(self.index_buffer.slice(..), IndexFormat::Uint32);
pass.draw_indexed(0..self.vertices_to_render, 0, 0..1);
Ok(())
}
}
fn next_copy_buffer_size(size: u64) -> u64 {
let next_power_of_2 = size.next_power_of_two() as u64;
let align_mask = COPY_BUFFER_ALIGNMENT - 1;
let padded_size = ((next_power_of_2 + align_mask) & !align_mask).max(COPY_BUFFER_ALIGNMENT);
padded_size
}
fn create_oversized_buffer(
device: &Device,
label: Option<&str>,
contents: &[u8],
usage: BufferUsages,
) -> (Buffer, u64) {
let size = next_copy_buffer_size(contents.len() as u64);
let buffer = device.create_buffer(&BufferDescriptor {
label,
size,
usage,
mapped_at_creation: true,
});
buffer.slice(..).get_mapped_range_mut()[..contents.len()].copy_from_slice(contents);
buffer.unmap();
(buffer, size)
}

209
src/text_atlas.rs Normal file
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@ -0,0 +1,209 @@
use etagere::{size2, BucketedAtlasAllocator};
use fontdue::layout::GlyphRasterConfig;
use std::{borrow::Cow, mem::size_of, num::NonZeroU64, sync::Arc};
use wgpu::{
BindGroup, BindGroupEntry, BindGroupLayoutEntry, BindingResource, BindingType, BlendState,
Buffer, BufferBindingType, BufferDescriptor, BufferUsages, ColorTargetState, ColorWrites,
Device, Extent3d, FilterMode, FragmentState, MultisampleState, PipelineLayoutDescriptor,
PrimitiveState, Queue, RenderPipeline, RenderPipelineDescriptor, SamplerBindingType,
SamplerDescriptor, ShaderModuleDescriptor, ShaderSource, ShaderStages, Texture,
TextureDescriptor, TextureDimension, TextureFormat, TextureSampleType, TextureUsages,
TextureViewDescriptor, TextureViewDimension, VertexFormat, VertexState,
};
use crate::{GlyphDetails, GlyphToRender, Params, RecentlyUsedMap, Resolution};
pub struct TextAtlas {
pub(crate) texture_pending: Vec<u8>,
pub(crate) texture: Texture,
pub(crate) packer: BucketedAtlasAllocator,
pub(crate) width: u32,
pub(crate) height: u32,
pub(crate) glyph_cache: RecentlyUsedMap<GlyphRasterConfig, GlyphDetails>,
pub(crate) params: Params,
pub(crate) params_buffer: Buffer,
pub(crate) pipeline: Arc<RenderPipeline>,
pub(crate) bind_group: Arc<BindGroup>,
}
impl TextAtlas {
pub fn new(device: &Device, _queue: &Queue, format: TextureFormat) -> Self {
let max_texture_dimension_2d = device.limits().max_texture_dimension_2d;
let width = max_texture_dimension_2d;
let height = max_texture_dimension_2d;
let packer = BucketedAtlasAllocator::new(size2(width as i32, height as i32));
// Create a texture to use for our atlas
let texture_pending = vec![0; (width * height) as usize];
let texture = device.create_texture(&TextureDescriptor {
label: Some("glyphon atlas"),
size: Extent3d {
width,
height,
depth_or_array_layers: 1,
},
mip_level_count: 1,
sample_count: 1,
dimension: TextureDimension::D2,
format: TextureFormat::R8Unorm,
usage: TextureUsages::TEXTURE_BINDING | TextureUsages::COPY_DST,
});
let texture_view = texture.create_view(&TextureViewDescriptor::default());
let sampler = device.create_sampler(&SamplerDescriptor {
label: Some("glyphon sampler"),
min_filter: FilterMode::Nearest,
mag_filter: FilterMode::Nearest,
mipmap_filter: FilterMode::Nearest,
lod_min_clamp: 0f32,
lod_max_clamp: 0f32,
..Default::default()
});
let glyph_cache = RecentlyUsedMap::new();
// Create a render pipeline to use for rendering later
let shader = device.create_shader_module(ShaderModuleDescriptor {
label: Some("glyphon shader"),
source: ShaderSource::Wgsl(Cow::Borrowed(include_str!("shader.wgsl"))),
});
let vertex_buffers = [wgpu::VertexBufferLayout {
array_stride: size_of::<GlyphToRender>() as wgpu::BufferAddress,
step_mode: wgpu::VertexStepMode::Vertex,
attributes: &[
wgpu::VertexAttribute {
format: VertexFormat::Uint32x2,
offset: 0,
shader_location: 0,
},
wgpu::VertexAttribute {
format: VertexFormat::Uint32,
offset: size_of::<u32>() as u64 * 2,
shader_location: 1,
},
wgpu::VertexAttribute {
format: VertexFormat::Uint32,
offset: size_of::<u32>() as u64 * 3,
shader_location: 2,
},
wgpu::VertexAttribute {
format: VertexFormat::Uint32,
offset: size_of::<u32>() as u64 * 4,
shader_location: 3,
},
],
}];
let bind_group_layout = device.create_bind_group_layout(&wgpu::BindGroupLayoutDescriptor {
entries: &[
BindGroupLayoutEntry {
binding: 0,
visibility: ShaderStages::VERTEX,
ty: BindingType::Buffer {
ty: BufferBindingType::Uniform,
has_dynamic_offset: false,
min_binding_size: NonZeroU64::new(size_of::<Params>() as u64),
},
count: None,
},
BindGroupLayoutEntry {
binding: 1,
visibility: ShaderStages::VERTEX | ShaderStages::FRAGMENT,
ty: BindingType::Texture {
multisampled: false,
view_dimension: TextureViewDimension::D2,
sample_type: TextureSampleType::Float { filterable: true },
},
count: None,
},
BindGroupLayoutEntry {
binding: 2,
visibility: ShaderStages::FRAGMENT,
ty: BindingType::Sampler(SamplerBindingType::Filtering),
count: None,
},
],
label: Some("glyphon bind group layout"),
});
let params = Params {
screen_resolution: Resolution {
width: 0,
height: 0,
},
_pad: [0, 0],
};
let params_buffer = device.create_buffer(&BufferDescriptor {
label: Some("glyphon params"),
size: size_of::<Params>() as u64,
usage: BufferUsages::UNIFORM | BufferUsages::COPY_DST,
mapped_at_creation: false,
});
let bind_group = Arc::new(device.create_bind_group(&wgpu::BindGroupDescriptor {
layout: &bind_group_layout,
entries: &[
BindGroupEntry {
binding: 0,
resource: params_buffer.as_entire_binding(),
},
BindGroupEntry {
binding: 1,
resource: BindingResource::TextureView(&texture_view),
},
BindGroupEntry {
binding: 2,
resource: BindingResource::Sampler(&sampler),
},
],
label: Some("glyphon bind group"),
}));
let pipeline_layout = device.create_pipeline_layout(&PipelineLayoutDescriptor {
label: None,
bind_group_layouts: &[&bind_group_layout],
push_constant_ranges: &[],
});
let pipeline = Arc::new(device.create_render_pipeline(&RenderPipelineDescriptor {
label: Some("glyphon pipeline"),
layout: Some(&pipeline_layout),
vertex: VertexState {
module: &shader,
entry_point: "vs_main",
buffers: &vertex_buffers,
},
fragment: Some(FragmentState {
module: &shader,
entry_point: "fs_main",
targets: &[Some(ColorTargetState {
format,
blend: Some(BlendState::PREMULTIPLIED_ALPHA_BLENDING),
write_mask: ColorWrites::default(),
})],
}),
primitive: PrimitiveState::default(),
depth_stencil: None,
multisample: MultisampleState {
count: 1,
mask: !0,
alpha_to_coverage_enabled: false,
},
multiview: None,
}));
Self {
texture_pending,
texture,
packer,
width,
height,
glyph_cache,
params,
params_buffer,
pipeline,
bind_group,
}
}
}

419
src/text_render.rs Normal file
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use etagere::{size2, Allocation};
use fontdue::{
layout::{GlyphRasterConfig, Layout},
Font,
};
use std::{collections::HashSet, iter, mem::size_of, num::NonZeroU32, slice};
use wgpu::{
Buffer, BufferDescriptor, BufferUsages, Device, Extent3d, ImageCopyTexture, ImageDataLayout,
IndexFormat, Origin3d, Queue, RenderPass, TextureAspect, COPY_BUFFER_ALIGNMENT,
};
use crate::{
GlyphDetails, GlyphToRender, GpuCache, HasColor, Params, PrepareError, RenderError, Resolution,
TextAtlas, TextOverflow,
};
pub struct TextRenderer {
vertex_buffer: Buffer,
vertex_buffer_size: u64,
index_buffer: Buffer,
index_buffer_size: u64,
vertices_to_render: u32,
glyphs_in_use: HashSet<GlyphRasterConfig>,
screen_resolution: Resolution,
}
impl TextRenderer {
pub fn new(device: &Device, _queue: &Queue) -> Self {
let vertex_buffer_size = next_copy_buffer_size(4096);
let vertex_buffer = device.create_buffer(&BufferDescriptor {
label: Some("glyphon vertices"),
size: vertex_buffer_size,
usage: BufferUsages::VERTEX | BufferUsages::COPY_DST,
mapped_at_creation: false,
});
let index_buffer_size = next_copy_buffer_size(4096);
let index_buffer = device.create_buffer(&BufferDescriptor {
label: Some("glyphon indices"),
size: index_buffer_size,
usage: BufferUsages::INDEX | BufferUsages::COPY_DST,
mapped_at_creation: false,
});
Self {
vertex_buffer,
vertex_buffer_size,
index_buffer,
index_buffer_size,
vertices_to_render: 0,
glyphs_in_use: HashSet::new(),
screen_resolution: Resolution {
width: 0,
height: 0,
},
}
}
pub fn prepare(
&mut self,
device: &Device,
queue: &Queue,
atlas: &mut TextAtlas,
screen_resolution: Resolution,
fonts: &[Font],
layouts: &[(Layout<impl HasColor>, TextOverflow)],
) -> Result<(), PrepareError> {
self.screen_resolution = screen_resolution;
let atlas_current_resolution = { atlas.params.screen_resolution };
if screen_resolution != atlas_current_resolution {
atlas.params.screen_resolution = screen_resolution;
queue.write_buffer(&atlas.params_buffer, 0, unsafe {
slice::from_raw_parts(
&atlas.params as *const Params as *const u8,
size_of::<Params>(),
)
});
}
struct UploadBounds {
x_min: usize,
x_max: usize,
y_min: usize,
y_max: usize,
}
let mut upload_bounds = None::<UploadBounds>;
self.glyphs_in_use.clear();
for (layout, _) in layouts.iter() {
for glyph in layout.glyphs() {
self.glyphs_in_use.insert(glyph.key);
let already_on_gpu = atlas.glyph_cache.contains_key(&glyph.key);
if already_on_gpu {
continue;
}
let font = &fonts[glyph.font_index];
let (metrics, bitmap) = font.rasterize_config(glyph.key);
let (gpu_cache, atlas_id) = if glyph.char_data.rasterize() {
// Find a position in the packer
let allocation = match try_allocate(atlas, metrics.width, metrics.height) {
Some(a) => a,
None => return Err(PrepareError::AtlasFull),
};
let atlas_min = allocation.rectangle.min;
let atlas_max = allocation.rectangle.max;
for row in 0..metrics.height {
let y_offset = atlas_min.y as usize;
let x_offset =
(y_offset + row) * atlas.width as usize + atlas_min.x as usize;
let bitmap_row = &bitmap[row * metrics.width..(row + 1) * metrics.width];
atlas.texture_pending[x_offset..x_offset + metrics.width]
.copy_from_slice(bitmap_row);
}
match upload_bounds.as_mut() {
Some(ub) => {
ub.x_min = ub.x_min.min(atlas_min.x as usize);
ub.x_max = ub.x_max.max(atlas_max.x as usize);
ub.y_min = ub.y_min.min(atlas_min.y as usize);
ub.y_max = ub.y_max.max(atlas_max.y as usize);
}
None => {
upload_bounds = Some(UploadBounds {
x_min: atlas_min.x as usize,
x_max: atlas_max.x as usize,
y_min: atlas_min.y as usize,
y_max: atlas_max.y as usize,
});
}
}
(
GpuCache::InAtlas {
x: atlas_min.x as u16,
y: atlas_min.y as u16,
},
Some(allocation.id),
)
} else {
(GpuCache::SkipRasterization, None)
};
if !atlas.glyph_cache.contains_key(&glyph.key) {
atlas.glyph_cache.insert(
glyph.key,
GlyphDetails {
width: metrics.width as u16,
height: metrics.height as u16,
gpu_cache,
atlas_id,
},
);
}
}
}
if let Some(ub) = upload_bounds {
queue.write_texture(
ImageCopyTexture {
texture: &atlas.texture,
mip_level: 0,
origin: Origin3d {
x: ub.x_min as u32,
y: ub.y_min as u32,
z: 0,
},
aspect: TextureAspect::All,
},
&atlas.texture_pending[ub.y_min * atlas.width as usize + ub.x_min..],
ImageDataLayout {
offset: 0,
bytes_per_row: NonZeroU32::new(atlas.width),
rows_per_image: NonZeroU32::new(atlas.height),
},
Extent3d {
width: (ub.x_max - ub.x_min) as u32,
height: (ub.y_max - ub.y_min) as u32,
depth_or_array_layers: 1,
},
);
}
let mut glyph_vertices = Vec::new();
let mut glyph_indices = Vec::new();
let mut glyphs_added = 0;
for (layout, overflow) in layouts.iter() {
let settings = layout.settings();
// Note: subpixel positioning is not currently handled, so we always use the nearest
// pixel.
let bounds_min_x = settings.x.round() as u32;
let bounds_max_x = settings
.max_width
.map(|w| bounds_min_x + w.round() as u32)
.unwrap_or(u32::MAX);
let bounds_min_y = settings.y.round() as u32;
let bounds_max_y = settings
.max_height
.map(|h| bounds_min_y + h.round() as u32)
.unwrap_or(u32::MAX);
for glyph in layout.glyphs() {
let mut x = glyph.x.round() as u32;
let mut y = glyph.y.round() as u32;
let details = atlas.glyph_cache.get(&glyph.key).unwrap();
let (mut atlas_x, mut atlas_y) = match details.gpu_cache {
GpuCache::InAtlas { x, y } => (x, y),
GpuCache::SkipRasterization => continue,
};
let mut width = details.width as u32;
let mut height = details.height as u32;
match overflow {
TextOverflow::Overflow => {}
TextOverflow::Hide => {
// Starts beyond right edge or ends beyond left edge
let max_x = x + width;
if x > bounds_max_x || max_x < bounds_min_x {
continue;
}
// Starts beyond bottom edge or ends beyond top edge
let max_y = y + height;
if y > bounds_max_y || max_y < bounds_min_y {
continue;
}
// Clip left ege
if x < bounds_min_x {
let right_shift = bounds_min_x - x;
x = bounds_min_x;
width = max_x - bounds_min_x;
atlas_x += right_shift as u16;
}
// Clip right edge
if x + width > bounds_max_x {
width = bounds_max_x - x;
}
// Clip top edge
if y < bounds_min_y {
let bottom_shift = bounds_min_y - y;
y = bounds_min_y;
height = max_y - bounds_min_y;
atlas_y += bottom_shift as u16;
}
// Clip bottom edge
if y + height > bounds_max_y {
height = bounds_max_y - y;
}
}
}
let color = glyph.user_data.color();
glyph_vertices.extend(
iter::repeat(GlyphToRender {
pos: [x, y],
dim: [width as u16, height as u16],
uv: [atlas_x, atlas_y],
color: [color.r, color.g, color.b, color.a],
})
.take(4),
);
let start = 4 * glyphs_added as u32;
glyph_indices.extend([start, start + 1, start + 2, start, start + 2, start + 3]);
glyphs_added += 1;
}
}
const VERTICES_PER_GLYPH: u32 = 6;
self.vertices_to_render = glyphs_added as u32 * VERTICES_PER_GLYPH;
let will_render = glyphs_added > 0;
if !will_render {
return Ok(());
}
let vertices = glyph_vertices.as_slice();
let vertices_raw = unsafe {
slice::from_raw_parts(
vertices as *const _ as *const u8,
size_of::<GlyphToRender>() * vertices.len(),
)
};
if self.vertex_buffer_size >= vertices_raw.len() as u64 {
queue.write_buffer(&self.vertex_buffer, 0, vertices_raw);
} else {
self.vertex_buffer.destroy();
let (buffer, buffer_size) = create_oversized_buffer(
device,
Some("glyphon vertices"),
vertices_raw,
BufferUsages::VERTEX | BufferUsages::COPY_DST,
);
self.vertex_buffer = buffer;
self.vertex_buffer_size = buffer_size;
}
let indices = glyph_indices.as_slice();
let indices_raw = unsafe {
slice::from_raw_parts(
indices as *const _ as *const u8,
size_of::<u32>() * indices.len(),
)
};
if self.index_buffer_size >= indices_raw.len() as u64 {
queue.write_buffer(&self.index_buffer, 0, indices_raw);
} else {
self.index_buffer.destroy();
let (buffer, buffer_size) = create_oversized_buffer(
device,
Some("glyphon indices"),
indices_raw,
BufferUsages::INDEX | BufferUsages::COPY_DST,
);
self.index_buffer = buffer;
self.index_buffer_size = buffer_size;
}
Ok(())
}
pub fn render<'pass>(
&'pass mut self,
atlas: &'pass TextAtlas,
pass: &mut RenderPass<'pass>,
) -> Result<(), RenderError> {
if self.vertices_to_render == 0 {
return Ok(());
}
{
// Validate that glyphs haven't been evicted from cache since `prepare`
for glyph in self.glyphs_in_use.iter() {
if !atlas.glyph_cache.contains_key(glyph) {
return Err(RenderError::RemovedFromAtlas);
}
}
// Validate that screen resolution hasn't changed since `prepare`
if self.screen_resolution != atlas.params.screen_resolution {
return Err(RenderError::ScreenResolutionChanged);
}
}
pass.set_pipeline(&atlas.pipeline);
pass.set_bind_group(0, &atlas.bind_group, &[]);
pass.set_vertex_buffer(0, self.vertex_buffer.slice(..));
pass.set_index_buffer(self.index_buffer.slice(..), IndexFormat::Uint32);
pass.draw_indexed(0..self.vertices_to_render, 0, 0..1);
Ok(())
}
}
fn try_allocate(atlas: &mut TextAtlas, width: usize, height: usize) -> Option<Allocation> {
let size = size2(width as i32, height as i32);
loop {
let allocation = atlas.packer.allocate(size);
if allocation.is_some() {
return allocation;
}
// Try to free least recently used allocation
let (key, value) = atlas.glyph_cache.pop()?;
atlas
.packer
.deallocate(value.atlas_id.expect("cache corrupt"));
atlas.glyph_cache.remove(&key);
}
}
fn next_copy_buffer_size(size: u64) -> u64 {
let align_mask = COPY_BUFFER_ALIGNMENT - 1;
((size.next_power_of_two() + align_mask) & !align_mask).max(COPY_BUFFER_ALIGNMENT)
}
fn create_oversized_buffer(
device: &Device,
label: Option<&str>,
contents: &[u8],
usage: BufferUsages,
) -> (Buffer, u64) {
let size = next_copy_buffer_size(contents.len() as u64);
let buffer = device.create_buffer(&BufferDescriptor {
label,
size,
usage,
mapped_at_creation: true,
});
buffer.slice(..).get_mapped_range_mut()[..contents.len()].copy_from_slice(contents);
buffer.unmap();
(buffer, size)
}