Auto merge of #1125 - msiglreith:corell, r=kvark

 Initial groundwork for a low level api

## Motivation
The next gen APIs (Vulkan and D3D12) offer an low level interface of the GPU in comparison to older APIs like OpenGL or D3D11. To avoid overhead due to high level abstraction we want to investigate the implementation of a thin wrapper above the mentioned low level APIs to address #1102.

## Goals
This PR creates a new low level core API `corell` and two backend implementations for the low level core. corell is heavily based on the vulkan API and shares a lot of concepts like `Instance`, `Surface`, etc., but tries to also take d3d12 into account. In future steps further abstractions could be considered to reduce the amount of setup code.

Planned coverage for this PR:
- [x] Instance/Context
- [x] Surface
- [x] Swapchain
- [x] PhysicalDevice

Note: Also includes some dummy types for other objects.
`format` and `memory` are mainly copied from `core`.

Hoping for early feedback if this is the intended way to go with regards to #1102.

cc @MaikKlein for quick checking ash based vulkan implementation if you have time 😄

Author: homu

Cargo.toml

@@ -11,7 +11,7 @@ documentation = "https://docs.rs/gfx"
 [features]
 default = []
 sdl = ["gfx_window_sdl"]
-vulkan = ["gfx_device_vulkan", "gfx_window_vulkan"]
+vulkan = ["gfx_device_vulkan", "gfx_device_vulkanll", "gfx_window_vulkan"]
 metal = ["gfx_device_metal", "gfx_window_metal"]
 unstable = []
 
@@ -25,6 +25,7 @@ env_logger = "0.3"
 glutin = "0.7.1"
 winit = "0.5.1"
 gfx_core = { path = "src/core", version = "0.6" }
+gfx_corell = { path = "src/corell", version = "0.1" }
 gfx = { path = "src/render", version = "0.14" }
 gfx_device_gl = { path = "src/backend/gl", version = "0.13" }
 gfx_window_glutin = { path = "src/window/glutin", version = "0.14" }
@@ -34,6 +35,11 @@ path = "src/backend/vulkan"
 version = "0.1"
 optional = true
 
+[dependencies.gfx_device_vulkanll]
+path = "src/backend/vulkanll"
+version = "0.1"
+optional = true
+
 [dependencies.gfx_window_vulkan]
 path = "src/window/vulkan"
 version = "0.1"
@@ -59,6 +65,7 @@ gfx_window_glfw = { path = "src/window/glfw", version = "0.13" }
 
 [target.'cfg(windows)'.dependencies]
 gfx_device_dx11 = { path = "src/backend/dx11", version = "0.5" }
+gfx_device_dx12ll = { path = "src/backend/dx12ll", version = "0.1" }
 gfx_window_dxgi = { path = "src/window/dxgi", version = "0.6" }
 
 [[example]]
@@ -121,6 +128,11 @@ path = "examples/mipmap/main.rs"
 name = "particle"
 path = "examples/particle/main.rs"
 
+[[example]]
+name = "trianglell"
+path = "examples/trianglell/main.rs"
+
+
 [dev_dependencies]
 cgmath = "0.7"
 gfx_gl = "0.3"

examples/trianglell/main.rs

@@ -0,0 +1,68 @@
+// Copyright 2017 The Gfx-rs Developers.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+extern crate env_logger;
+extern crate gfx_corell;
+#[cfg(all(target_os = "windows", not(feature = "vulkan")))]
+extern crate gfx_device_dx12ll as back;
+#[cfg(feature = "vulkan")]
+extern crate gfx_device_vulkanll as back;
+
+extern crate winit;
+
+use gfx_corell::{Instance, Adapter, Surface, SwapChain, QueueFamily};
+
+pub type ColorFormat = gfx_corell::format::Rgba8;
+
+fn main() {
+    env_logger::init().unwrap();
+    let window = winit::WindowBuilder::new()
+        .with_dimensions(1024, 768)
+        .with_title("triangle (Low Level)".to_string())
+        .build()
+        .unwrap();
+
+    // instantiate backend
+    let instance = back::Instance::create();
+    let physical_devices = instance.enumerate_adapters();
+    let surface = instance.create_surface(&window);
+
+    let queue_descs = physical_devices[0].get_queue_families().map(|family| { (family, family.num_queues()) });
+    
+    for device in &physical_devices {
+        println!("{:?}", device.get_info());
+    }
+
+    // build a new device and associated command queues
+    let (device, queues) = physical_devices[0].open(queue_descs);
+
+    let mut swap_chain = surface.build_swapchain::<ColorFormat>(&queues[0]);
+
+    'main: loop {
+        for event in window.poll_events() {
+            match event {
+                winit::Event::KeyboardInput(_, _, Some(winit::VirtualKeyCode::Escape)) |
+                winit::Event::Closed => break 'main,
+                _ => {},
+            }
+        }
+
+        let frame = swap_chain.acquire_frame();
+
+        // rendering
+
+        // present frame
+        swap_chain.present();
+    }
+}

src/backend/dx12ll/Cargo.toml

@@ -0,0 +1,37 @@
+
+# Copyright 2016 The Gfx-rs Developers.
+#
+# Licensed under the Apache License, Version 2.0 (the "License");
+# you may not use this file except in compliance with the License.
+# You may obtain a copy of the License at
+#
+#     http://www.apache.org/licenses/LICENSE-2.0
+#
+# Unless required by applicable law or agreed to in writing, software
+# distributed under the License is distributed on an "AS IS" BASIS,
+# WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+# See the License for the specific language governing permissions and
+# limitations under the License.
+
+[package]
+name = "gfx_device_dx12ll"
+version = "0.1.0"
+description = "DirectX-12 (Low Level) backend for gfx-rs"
+homepage = "https://github.com/gfx-rs/gfx"
+repository = "https://github.com/gfx-rs/gfx"
+keywords = ["graphics", "gamedev"]
+license = "Apache-2.0"
+authors = ["The Gfx-rs Developers"]
+
+[lib]
+name = "gfx_device_dx12ll"
+
+[dependencies]
+log = "0.3"
+gfx_corell = { path = "../../corell", version = "0.1.0" }
+d3d12-sys = "0.2"
+dxgi-sys = "0.2"
+dxguid-sys = "0.2"
+comptr = { git = "https://github.com/msiglreith/comptr-rs.git" }
+winapi = "0.2"
+winit = "0.5"

src/backend/dx12ll/src/data.rs

@@ -0,0 +1,129 @@
+// Copyright 2017 The Gfx-rs Developers.
+//
+// Licensed under the Apache License, Version 2.0 (the "License");
+// you may not use this file except in compliance with the License.
+// You may obtain a copy of the License at
+//
+//     http://www.apache.org/licenses/LICENSE-2.0
+//
+// Unless required by applicable law or agreed to in writing, software
+// distributed under the License is distributed on an "AS IS" BASIS,
+// WITHOUT WARRANTIES OR CONDITIONS OF ANY KIND, either express or implied.
+// See the License for the specific language governing permissions and
+// limitations under the License.
+
+use core::format::Format;
+use winapi::*;
+
+pub fn map_format(format: Format, is_target: bool) -> Option<DXGI_FORMAT> {
+    use core::format::SurfaceType::*;
+    use core::format::ChannelType::*;
+    Some(match format.0 {
+        R4_G4 | R4_G4_B4_A4 | R5_G5_B5_A1 | R5_G6_B5 => return None,
+        R8 => match format.1 {
+            Int   => DXGI_FORMAT_R8_SINT,
+            Uint  => DXGI_FORMAT_R8_UINT,
+            Inorm => DXGI_FORMAT_R8_SNORM,
+            Unorm => DXGI_FORMAT_R8_UNORM,
+            _ => return None,
+        },
+        R8_G8 => match format.1 {
+            Int   => DXGI_FORMAT_R8G8_SINT,
+            Uint  => DXGI_FORMAT_R8G8_UINT,
+            Inorm => DXGI_FORMAT_R8G8_SNORM,
+            Unorm => DXGI_FORMAT_R8G8_UNORM,
+            _ => return None,
+        },
+        R8_G8_B8_A8 => match format.1 {
+            Int   => DXGI_FORMAT_R8G8B8A8_SINT,
+            Uint  => DXGI_FORMAT_R8G8B8A8_UINT,
+            Inorm => DXGI_FORMAT_R8G8B8A8_SNORM,
+            Unorm => DXGI_FORMAT_R8G8B8A8_UNORM,
+            Srgb  => DXGI_FORMAT_R8G8B8A8_UNORM_SRGB,
+            _ => return None,
+        },
+        R10_G10_B10_A2 => match format.1 {
+            Uint  => DXGI_FORMAT_R10G10B10A2_UINT,
+            Unorm => DXGI_FORMAT_R10G10B10A2_UNORM,
+            _ => return None,
+        },
+        R11_G11_B10 => match format.1 {
+            Float => DXGI_FORMAT_R11G11B10_FLOAT,
+            _ => return None,
+        },
+        R16 => match format.1 {
+            Int   => DXGI_FORMAT_R16_SINT,
+            Uint  => DXGI_FORMAT_R16_UINT,
+            Inorm => DXGI_FORMAT_R16_SNORM,
+            Unorm => DXGI_FORMAT_R16_UNORM,
+            Float => DXGI_FORMAT_R16_FLOAT,
+            _ => return None,
+        },
+        R16_G16 => match format.1 {
+            Int   => DXGI_FORMAT_R16G16_SINT,
+            Uint  => DXGI_FORMAT_R16G16_UINT,
+            Inorm => DXGI_FORMAT_R16G16_SNORM,
+            Unorm => DXGI_FORMAT_R16G16_UNORM,
+            Float => DXGI_FORMAT_R16G16_FLOAT,
+            _ => return None,
+        },
+        R16_G16_B16 => return None,
+        R16_G16_B16_A16 => match format.1 {
+            Int   => DXGI_FORMAT_R16G16B16A16_SINT,
+            Uint  => DXGI_FORMAT_R16G16B16A16_UINT,
+            Inorm => DXGI_FORMAT_R16G16B16A16_SNORM,
+            Unorm => DXGI_FORMAT_R16G16B16A16_UNORM,
+            Float => DXGI_FORMAT_R16G16B16A16_FLOAT,
+            _ => return None,
+        },
+        R32 => match format.1 {
+            Int   => DXGI_FORMAT_R32_SINT,
+            Uint  => DXGI_FORMAT_R32_UINT,
+            Float => DXGI_FORMAT_R32_FLOAT,
+            _ => return None,
+        },
+        R32_G32 => match format.1 {
+            Int   => DXGI_FORMAT_R32G32_SINT,
+            Uint  => DXGI_FORMAT_R32G32_UINT,
+            Float => DXGI_FORMAT_R32G32_FLOAT,
+            _ => return None,
+        },
+        R32_G32_B32 => match format.1 {
+            Int   => DXGI_FORMAT_R32G32B32_SINT,
+            Uint  => DXGI_FORMAT_R32G32B32_UINT,
+            Float => DXGI_FORMAT_R32G32B32_FLOAT,
+            _ => return None,
+        },
+        R32_G32_B32_A32 => match format.1 {
+            Int   => DXGI_FORMAT_R32G32B32A32_SINT,
+            Uint  => DXGI_FORMAT_R32G32B32A32_UINT,
+            Float => DXGI_FORMAT_R32G32B32A32_FLOAT,
+            _ => return None,
+        },
+        B8_G8_R8_A8 => match format.1 {
+            Unorm => DXGI_FORMAT_B8G8R8A8_UNORM,
+            _ => return None,
+        },
+        D16 => match (is_target, format.1) {
+            (true, _)      => DXGI_FORMAT_D16_UNORM,
+            (false, Unorm) => DXGI_FORMAT_R16_UNORM,
+            _ => return None,
+        },
+        D24 => match (is_target, format.1) {
+            (true, _)      => DXGI_FORMAT_D24_UNORM_S8_UINT,
+            (false, Unorm) => DXGI_FORMAT_R24_UNORM_X8_TYPELESS,
+            _ => return None,
+        },
+        D24_S8 => match (is_target, format.1) {
+            (true, _)      => DXGI_FORMAT_D24_UNORM_S8_UINT,
+            (false, Unorm) => DXGI_FORMAT_R24_UNORM_X8_TYPELESS,
+            (false, Uint)  => DXGI_FORMAT_X24_TYPELESS_G8_UINT,
+            _ => return None,
+        },
+        D32 => match (is_target, format.1) {
+            (true, _)      => DXGI_FORMAT_D32_FLOAT,
+            (false, Float) => DXGI_FORMAT_R32_FLOAT,
+            _ => return None,
+        },
+    })
+}