4 files changed, 382 insertions, 0 deletions
diff --git a/stockton-render/src/buffers/dedicated_image.rs b/stockton-render/src/buffers/dedicated_image.rs
new file mode 100644
index 0000000..bf49a38
--- /dev/null
+++ b/stockton-render/src/buffers/dedicated_image.rs
@@ -0,0 +1,134 @@
+//! A dedicated image. Used for depth buffers.
+
+use crate::texture::PIXEL_SIZE;
+use crate::types::*;
+
+use std::mem::ManuallyDrop;
+
+use anyhow::{Context, Result};
+use hal::{
+    format::{Format, Swizzle},
+    image::{SubresourceRange, Usage, Usage as ImgUsage, ViewKind},
+    memory,
+    memory::Properties,
+    MemoryTypeId,
+};
+use thiserror::Error;
+
+/// Holds an image that's loaded into GPU memory dedicated only to that image, bypassing the memory allocator.
+pub struct DedicatedLoadedImage {
+    /// The GPU Image handle
+    image: ManuallyDrop<ImageT>,
+
+    /// The full view of the image
+    pub image_view: ManuallyDrop<ImageViewT>,
+
+    /// The memory backing the image
+    memory: ManuallyDrop<MemoryT>,
+}
+
+#[derive(Debug, Error)]
+pub enum ImageLoadError {
+    #[error("No suitable memory type for image memory")]
+    NoMemoryTypes,
+}
+
+impl DedicatedLoadedImage {
+    pub fn new(
+        device: &mut DeviceT,
+        adapter: &Adapter,
+        format: Format,
+        usage: Usage,
+        resources: SubresourceRange,
+        width: usize,
+        height: usize,
+    ) -> Result<DedicatedLoadedImage> {
+        let (memory, image_ref) = {
+            // Round up the size to align properly
+            let initial_row_size = PIXEL_SIZE * width;
+            let limits = adapter.physical_device.properties().limits;
+            let row_alignment_mask = limits.optimal_buffer_copy_pitch_alignment as u32 - 1;
+
+            let row_size =
+                ((initial_row_size as u32 + row_alignment_mask) & !row_alignment_mask) as usize;
+            debug_assert!(row_size as usize >= initial_row_size);
+
+            // Make the image
+            let mut image_ref = unsafe {
+                use hal::image::{Kind, Tiling, ViewCapabilities};
+
+                device.create_image(
+                    Kind::D2(width as u32, height as u32, 1, 1),
+                    1,
+                    format,
+                    Tiling::Optimal,
+                    usage,
+                    memory::SparseFlags::empty(),
+                    ViewCapabilities::empty(),
+                )
+            }
+            .context("Error creating image")?;
+
+            // Allocate memory
+            let memory = unsafe {
+                let requirements = device.get_image_requirements(&image_ref);
+
+                let memory_type_id = adapter
+                    .physical_device
+                    .memory_properties()
+                    .memory_types
+                    .iter()
+                    .enumerate()
+                    .find(|&(id, memory_type)| {
+                        requirements.type_mask & (1 << id) != 0
+                            && memory_type.properties.contains(Properties::DEVICE_LOCAL)
+                    })
+                    .map(|(id, _)| MemoryTypeId(id))
+                    .ok_or(ImageLoadError::NoMemoryTypes)?;
+
+                let memory = device
+                    .allocate_memory(memory_type_id, requirements.size)
+                    .context("Error allocating memory for image")?;
+
+                device
+                    .bind_image_memory(&memory, 0, &mut image_ref)
+                    .context("Error binding memory to image")?;
+
+                memory
+            };
+
+            (memory, image_ref)
+        };
+
+        // Create ImageView and sampler
+        let image_view = unsafe {
+            device.create_image_view(
+                &image_ref,
+                ViewKind::D2,
+                format,
+                Swizzle::NO,
+                ImgUsage::DEPTH_STENCIL_ATTACHMENT,
+                resources,
+            )
+        }
+        .context("Error creating image view")?;
+
+        Ok(DedicatedLoadedImage {
+            image: ManuallyDrop::new(image_ref),
+            image_view: ManuallyDrop::new(image_view),
+            memory: ManuallyDrop::new(memory),
+        })
+    }
+
+    /// Properly frees/destroys all the objects in this struct
+    /// Dropping without doing this is a bad idea
+    pub fn deactivate(self, device: &mut DeviceT) {
+        unsafe {
+            use core::ptr::read;
+
+            device.destroy_image_view(ManuallyDrop::into_inner(read(&self.image_view)));
+            device.destroy_image(ManuallyDrop::into_inner(read(&self.image)));
+            device.free_memory(ManuallyDrop::into_inner(read(&self.memory)));
+        }
+    }
+}
diff --git a/stockton-render/src/buffers/draw_buffers.rs b/stockton-render/src/buffers/draw_buffers.rs
new file mode 100644
index 0000000..5baec92
--- /dev/null
+++ b/stockton-render/src/buffers/draw_buffers.rs
@@ -0,0 +1,43 @@
+//! A vertex and index buffer set for drawing
+
+use super::StagedBuffer;
+use crate::types::*;
+
+use anyhow::{Context, Result};
+use hal::buffer::Usage;
+use std::mem::ManuallyDrop;
+
+/// Initial size of vertex buffer. TODO: Way of overriding this
+pub const INITIAL_VERT_SIZE: u64 = 3 * 3000;
+
+/// Initial size of index buffer. TODO: Way of overriding this
+pub const INITIAL_INDEX_SIZE: u64 = 3000;
+
+/// The buffers used for drawing, ie index and vertex buffer
+pub struct DrawBuffers<'a, T: Sized> {
+    pub vertex_buffer: ManuallyDrop<StagedBuffer<'a, T>>,
+    pub index_buffer: ManuallyDrop<StagedBuffer<'a, (u16, u16, u16)>>,
+}
+
+impl<'a, T> DrawBuffers<'a, T> {
+    pub fn new(device: &mut DeviceT, adapter: &Adapter) -> Result<DrawBuffers<'a, T>> {
+        let vert = StagedBuffer::new(device, adapter, Usage::VERTEX, INITIAL_VERT_SIZE)
+            .context("Error creating vertex buffer")?;
+        let index = StagedBuffer::new(device, adapter, Usage::INDEX, INITIAL_INDEX_SIZE)
+            .context("Error creating index buffer")?;
+
+        Ok(DrawBuffers {
+            vertex_buffer: ManuallyDrop::new(vert),
+            index_buffer: ManuallyDrop::new(index),
+        })
+    }
+
+    pub fn deactivate(self, device: &mut DeviceT) {
+        unsafe {
+            use core::ptr::read;
+
+            ManuallyDrop::into_inner(read(&self.vertex_buffer)).deactivate(device);
+            ManuallyDrop::into_inner(read(&self.index_buffer)).deactivate(device);
+        }
+    }
+}
diff --git a/stockton-render/src/buffers/mod.rs b/stockton-render/src/buffers/mod.rs
new file mode 100644
index 0000000..82ca62a
--- /dev/null
+++ b/stockton-render/src/buffers/mod.rs
@@ -0,0 +1,63 @@
+//! All sorts of buffers
+
+use std::ops::IndexMut;
+
+use crate::{error::EnvironmentError, types::*};
+
+use anyhow::{Context, Result};
+use hal::{
+    buffer::Usage,
+    memory::{Properties, SparseFlags},
+    MemoryTypeId,
+};
+
+mod dedicated_image;
+mod draw_buffers;
+mod staged;
+
+pub use dedicated_image::*;
+pub use draw_buffers::*;
+pub use staged::*;
+
+/// Create a buffer of the given specifications, allocating more device memory.
+// TODO: Use a different memory allocator?
+pub(crate) fn create_buffer(
+    device: &mut DeviceT,
+    adapter: &Adapter,
+    usage: Usage,
+    properties: Properties,
+    size: u64,
+) -> Result<(BufferT, MemoryT)> {
+    let mut buffer = unsafe { device.create_buffer(size, usage, SparseFlags::empty()) }
+        .context("Error creating buffer")?;
+
+    let requirements = unsafe { device.get_buffer_requirements(&buffer) };
+    let memory_type_id = adapter
+        .physical_device
+        .memory_properties()
+        .memory_types
+        .iter()
+        .enumerate()
+        .find(|&(id, memory_type)| {
+            requirements.type_mask & (1 << id) != 0 && memory_type.properties.contains(properties)
+        })
+        .map(|(id, _)| MemoryTypeId(id))
+        .ok_or(EnvironmentError::NoMemoryTypes)?;
+
+    let memory = unsafe { device.allocate_memory(memory_type_id, requirements.size) }
+        .context("Error allocating memory")?;
+
+    unsafe { device.bind_buffer_memory(&memory, 0, &mut buffer) }
+        .context("Error binding memory to buffer")?;
+
+    Ok((buffer, memory))
+}
+
+/// A buffer that can be modified by the CPU
+pub trait ModifiableBuffer: IndexMut<usize> {
+    /// Get a handle to the underlying GPU buffer
+    fn get_buffer(&mut self) -> &BufferT;
+
+    /// Record the command(s) required to commit changes to this buffer to the given command buffer.
+    fn record_commit_cmds<'a>(&'a mut self, cmd_buffer: &mut CommandBufferT) -> Result<()>;
+}
diff --git a/stockton-render/src/buffers/staged.rs b/stockton-render/src/buffers/staged.rs
new file mode 100644
index 0000000..71b5204
--- /dev/null
+++ b/stockton-render/src/buffers/staged.rs
@@ -0,0 +1,142 @@
+//! A buffer that can be written to by the CPU using staging memory
+
+use super::{create_buffer, ModifiableBuffer};
+use crate::types::*;
+
+use core::mem::{size_of, ManuallyDrop};
+use std::{
+    convert::TryInto,
+    ops::{Index, IndexMut},
+};
+
+use anyhow::{Context, Result};
+use hal::{
+    buffer::Usage,
+    command::BufferCopy,
+    memory::{Properties, Segment},
+};
+
+/// A GPU buffer that is written to using a staging buffer
+pub struct StagedBuffer<'a, T: Sized> {
+    /// CPU-visible buffer
+    staged_buffer: ManuallyDrop<BufferT>,
+
+    /// CPU-visible memory
+    staged_memory: ManuallyDrop<MemoryT>,
+
+    /// GPU Buffer
+    buffer: ManuallyDrop<BufferT>,
+
+    /// GPU Memory
+    memory: ManuallyDrop<MemoryT>,
+
+    /// Where staged buffer is mapped in CPU memory
+    staged_mapped_memory: &'a mut [T],
+
+    /// The highest index in the buffer that's been written to.
+    pub highest_used: usize,
+}
+
+impl<'a, T: Sized> StagedBuffer<'a, T> {
+    /// size is the size in T
+    pub fn new(device: &mut DeviceT, adapter: &Adapter, usage: Usage, size: u64) -> Result<Self> {
+        // Convert size to bytes
+        let size_bytes = size * size_of::<T>() as u64;
+
+        // Get CPU-visible buffer
+        let (staged_buffer, mut staged_memory) = create_buffer(
+            device,
+            adapter,
+            Usage::TRANSFER_SRC,
+            Properties::CPU_VISIBLE,
+            size_bytes,
+        )
+        .context("Error creating staging buffer")?;
+
+        // Get GPU Buffer
+        let (buffer, memory) = create_buffer(
+            device,
+            adapter,
+            Usage::TRANSFER_DST | usage,
+            Properties::DEVICE_LOCAL | Properties::COHERENT,
+            size_bytes,
+        )
+        .context("Error creating GPU buffer")?;
+
+        // Map it somewhere and get a slice to that memory
+        let staged_mapped_memory = unsafe {
+            let ptr = device
+                .map_memory(
+                    &mut staged_memory,
+                    Segment {
+                        offset: 0,
+                        size: Some(size_bytes),
+                    },
+                )
+                .context("Error mapping staged memory")?;
+
+            std::slice::from_raw_parts_mut(ptr as *mut T, size.try_into()?)
+        };
+
+        Ok(StagedBuffer {
+            staged_buffer: ManuallyDrop::new(staged_buffer),
+            staged_memory: ManuallyDrop::new(staged_memory),
+            buffer: ManuallyDrop::new(buffer),
+            memory: ManuallyDrop::new(memory),
+            staged_mapped_memory,
+            highest_used: 0,
+        })
+    }
+
+    /// Call this before dropping
+    pub(crate) fn deactivate(mut self, device: &mut DeviceT) {
+        unsafe {
+            device.unmap_memory(&mut self.staged_memory);
+
+            device.free_memory(ManuallyDrop::take(&mut self.staged_memory));
+            device.destroy_buffer(ManuallyDrop::take(&mut self.staged_buffer));
+
+            device.free_memory(ManuallyDrop::take(&mut self.memory));
+            device.destroy_buffer(ManuallyDrop::take(&mut self.buffer));
+        };
+    }
+}
+
+impl<'a, T: Sized> ModifiableBuffer for StagedBuffer<'a, T> {
+    fn get_buffer(&mut self) -> &BufferT {
+        &self.buffer
+    }
+
+    fn record_commit_cmds(&mut self, buf: &mut CommandBufferT) -> Result<()> {
+        unsafe {
+            buf.copy_buffer(
+                &self.staged_buffer,
+                &self.buffer,
+                std::iter::once(BufferCopy {
+                    src: 0,
+                    dst: 0,
+                    size: ((self.highest_used + 1) * size_of::<T>()) as u64,
+                }),
+            );
+        }
+
+        Ok(())
+    }
+}
+
+impl<'a, T: Sized> Index<usize> for StagedBuffer<'a, T> {
+    type Output = T;
+
+    fn index(&self, index: usize) -> &Self::Output {
+        &self.staged_mapped_memory[index]
+    }
+}
+
+impl<'a, T: Sized> IndexMut<usize> for StagedBuffer<'a, T> {
+    fn index_mut(&mut self, index: usize) -> &mut Self::Output {
+        if index > self.highest_used {
+            self.highest_used = index;
+        }
+        &mut self.staged_mapped_memory[index]
+    }
+}