vee_wgpu 0.2.0

//! Holding texture data in GPU VRAM.

use std::error::Error;
use std::fmt::Debug;

use glam::UVec2;
use image::GenericImageView;
use wgpu::TextureFormat;

/// Contains pointers to the texture in VRAM, a view of the texture, and a sampler of the texture.
/// These are often stored together during rendering.
pub struct TextureBundle {
    #[allow(unused)]
    pub texture: wgpu::Texture,
    pub view: wgpu::TextureView,
    pub sampler: wgpu::Sampler,
}
impl Debug for TextureBundle {
    fn fmt(&self, f: &mut std::fmt::Formatter<'_>) -> std::fmt::Result {
        f.debug_struct("Texture").finish()
    }
}

#[allow(unused)]
impl TextureBundle {
    pub fn from_bytes(
        device: &wgpu::Device,
        queue: &wgpu::Queue,
        bytes: &[u8],
        label: &str,
    ) -> Result<Self, Box<dyn Error>> {
        let img = image::load_from_memory(bytes)?;
        Self::from_image(device, queue, &img, Some(label))
    }

    pub fn from_image(
        device: &wgpu::Device,
        queue: &wgpu::Queue,
        img: &image::DynamicImage,
        label: Option<&str>,
    ) -> Result<Self, Box<dyn Error>> {
        let rgba = img.to_rgba8();
        let dimensions = img.dimensions();

        let size = wgpu::Extent3d {
            width: dimensions.0,
            height: dimensions.1,
            depth_or_array_layers: 1,
        };
        let texture = device.create_texture(&wgpu::TextureDescriptor {
            label,
            size,
            mip_level_count: 1,
            sample_count: 1,
            dimension: wgpu::TextureDimension::D2,
            format: TextureFormat::Rgba8UnormSrgb,
            usage: wgpu::TextureUsages::TEXTURE_BINDING | wgpu::TextureUsages::COPY_DST,
            view_formats: &[],
        });

        queue.write_texture(
            wgpu::TexelCopyTextureInfo {
                aspect: wgpu::TextureAspect::All,
                texture: &texture,
                mip_level: 0,
                origin: wgpu::Origin3d::ZERO,
            },
            &rgba,
            wgpu::TexelCopyBufferLayout {
                offset: 0,
                bytes_per_row: Some(4 * dimensions.0),
                rows_per_image: Some(dimensions.1),
            },
            size,
        );

        let view = texture.create_view(&wgpu::TextureViewDescriptor::default());
        let sampler = device.create_sampler(&wgpu::SamplerDescriptor {
            address_mode_u: wgpu::AddressMode::ClampToEdge,
            address_mode_v: wgpu::AddressMode::ClampToEdge,
            address_mode_w: wgpu::AddressMode::ClampToEdge,
            mag_filter: wgpu::FilterMode::Linear,
            min_filter: wgpu::FilterMode::Nearest,
            mipmap_filter: wgpu::FilterMode::Nearest,
            ..Default::default()
        });

        Ok(Self {
            texture,
            view,
            sampler,
        })
    }

    pub const DEPTH_FORMAT: TextureFormat = TextureFormat::Depth32Float; // 1.

    pub fn create_depth_texture(device: &wgpu::Device, size: &UVec2, label: &str) -> Self {
        let size = wgpu::Extent3d {
            // 2.
            width: size.x.max(1),
            height: size.y.max(1),
            depth_or_array_layers: 1,
        };
        let desc = wgpu::TextureDescriptor {
            label: Some(label),
            size,
            mip_level_count: 1,
            sample_count: 1,
            dimension: wgpu::TextureDimension::D2,
            format: Self::DEPTH_FORMAT,
            usage: wgpu::TextureUsages::RENDER_ATTACHMENT // 3.
                    | wgpu::TextureUsages::TEXTURE_BINDING,
            view_formats: &[],
        };
        let texture = device.create_texture(&desc);

        let view = texture.create_view(&wgpu::TextureViewDescriptor::default());
        let sampler = device.create_sampler(&wgpu::SamplerDescriptor {
            // 4.
            address_mode_u: wgpu::AddressMode::ClampToEdge,
            address_mode_v: wgpu::AddressMode::ClampToEdge,
            address_mode_w: wgpu::AddressMode::ClampToEdge,
            mag_filter: wgpu::FilterMode::Linear,
            min_filter: wgpu::FilterMode::Linear,
            mipmap_filter: wgpu::FilterMode::Nearest,
            compare: Some(wgpu::CompareFunction::LessEqual), // 5.
            lod_min_clamp: 0.0,
            lod_max_clamp: 100.0,
            ..Default::default()
        });

        Self {
            texture,
            view,
            sampler,
        }
    }

    /// Outputs a linear color texture instead of a Srgb color texture. Should replace.
    pub fn create_texture_linear_color(device: &wgpu::Device, size: &UVec2, label: &str) -> Self {
        let size = wgpu::Extent3d {
            // 2.
            width: size.x.max(1),
            height: size.y.max(1),
            depth_or_array_layers: 1,
        };
        let desc = wgpu::TextureDescriptor {
            label: Some(label),
            size,
            mip_level_count: 1,
            sample_count: 1,
            dimension: wgpu::TextureDimension::D2,
            format: TextureFormat::Bgra8Unorm,
            usage: wgpu::TextureUsages::RENDER_ATTACHMENT // 3.
                    | wgpu::TextureUsages::TEXTURE_BINDING
                    | wgpu::TextureUsages::COPY_SRC,
            view_formats: &[TextureFormat::Bgra8Unorm, TextureFormat::Bgra8UnormSrgb],
        };
        let texture = device.create_texture(&desc);

        let view = texture.create_view(&wgpu::TextureViewDescriptor::default());
        let sampler = device.create_sampler(&wgpu::SamplerDescriptor {
            // 4.
            address_mode_u: wgpu::AddressMode::MirrorRepeat,
            address_mode_v: wgpu::AddressMode::MirrorRepeat,
            address_mode_w: wgpu::AddressMode::MirrorRepeat,
            mag_filter: wgpu::FilterMode::Linear,
            min_filter: wgpu::FilterMode::Linear,
            mipmap_filter: wgpu::FilterMode::Nearest,
            lod_min_clamp: 0.0,
            lod_max_clamp: 100.0,
            ..Default::default()
        });

        Self {
            texture,
            view,
            sampler,
        }
    }

    pub fn create_texture(device: &wgpu::Device, size: &UVec2, label: &str) -> Self {
        let size = wgpu::Extent3d {
            // 2.
            width: size.x.max(1),
            height: size.y.max(1),
            depth_or_array_layers: 1,
        };
        let desc = wgpu::TextureDescriptor {
            label: Some(label),
            size,
            mip_level_count: 1,
            sample_count: 1,
            dimension: wgpu::TextureDimension::D2,
            format: TextureFormat::Bgra8UnormSrgb,
            usage: wgpu::TextureUsages::RENDER_ATTACHMENT // 3.
                    | wgpu::TextureUsages::TEXTURE_BINDING
                    | wgpu::TextureUsages::COPY_SRC,
            view_formats: &[TextureFormat::Bgra8Unorm, TextureFormat::Bgra8UnormSrgb],
        };
        let texture = device.create_texture(&desc);

        let view = texture.create_view(&wgpu::TextureViewDescriptor::default());
        let sampler = device.create_sampler(&wgpu::SamplerDescriptor {
            // 4.
            address_mode_u: wgpu::AddressMode::MirrorRepeat,
            address_mode_v: wgpu::AddressMode::MirrorRepeat,
            address_mode_w: wgpu::AddressMode::MirrorRepeat,
            mag_filter: wgpu::FilterMode::Linear,
            min_filter: wgpu::FilterMode::Linear,
            mipmap_filter: wgpu::FilterMode::Nearest,
            lod_min_clamp: 0.0,
            lod_max_clamp: 100.0,
            ..Default::default()
        });

        Self {
            texture,
            view,
            sampler,
        }
    }
}