Clean up the 3D renderer for enhanced flexibility (#1895)

* Give `GPU2D::Unit` a virtual destructor

- Undefined behavior avoided!

* Add an `array2d` alias

* Move various parts of `GPU2D::SoftRenderer` to `constexpr`

- `SoftRenderer::MosaicTable` is now initialized at compile-time
- Most of the `SoftRenderer::Color*` functions are now `constexpr`
- The aforementioned functions are used with a constant value in at least one place, so they'll be at least partially computed at compile-time

* Generalize `GLRenderer::PrepareCaptureFrame`

- Declare it in the base `Renderer3D` class, but make it empty

* Remove unneeded `virtual` specifiers

* Store `Framebuffer`'s memory in `unique_ptr`s

- Reduce the risk of leaks this way

* Clean up how `GLCompositor` is initialized

- Return it as an `std::optional` instead of a `std::unique_ptr`
- Make `GLCompositor` movable
- Replace `GLCompositor`'s plain arrays with `std::array` to simplify moving

* Pass `GPU` to `GLCompositor`'s important functions instead of passing it to the constructor

* Move `GLCompositor` to be a field within `GLRenderer`

- Some methods were moved up and made `virtual`

* Fix some linker errors

* Set the renderer in the frontend

* Remove unneeded `virtual` specifiers

* Remove `RenderSettings` in favor of just exposing the relevant member variables

* Update the frontend to accommodate the core changes

* Add `constexpr` and `const` to places in the interpolator

* Qualify references to `size_t`

* Construct the `optional` directly instead of using `make_optional`

- It makes the Linux build choke
- I think it's because `GLCompositor`'s constructor is `private`

1 files changed, 8 insertions, 6 deletions

diff --git a/src/GPU3D_Soft.cpp b/src/GPU3D_Soft.cpp
index 809bd59..03c6265 100644
--- a/src/GPU3D_Soft.cpp
+++ b/src/GPU3D_Soft.cpp
@@ -71,14 +71,13 @@ void SoftRenderer::SetupRenderThread()
 }
 
 
-SoftRenderer::SoftRenderer(melonDS::GPU& gpu) noexcept
-    : Renderer3D(false), GPU(gpu)
+SoftRenderer::SoftRenderer(melonDS::GPU& gpu, bool threaded) noexcept
+    : Renderer3D(false), GPU(gpu), Threaded(threaded)
 {
     Sema_RenderStart = Platform::Semaphore_Create();
     Sema_RenderDone = Platform::Semaphore_Create();
     Sema_ScanlineCount = Platform::Semaphore_Create();
 
-    Threaded = false;
     RenderThreadRunning = false;
     RenderThreadRendering = false;
     RenderThread = nullptr;
@@ -104,10 +103,13 @@ void SoftRenderer::Reset()
     SetupRenderThread();
 }
 
-void SoftRenderer::SetRenderSettings(const RenderSettings& settings) noexcept
+void SoftRenderer::SetThreaded(bool threaded) noexcept
 {
-    Threaded = settings.Soft_Threaded;
-    SetupRenderThread();
+    if (Threaded != threaded)
+    {
+        Threaded = threaded;
+        SetupRenderThread();
+    }
 }
 
 void SoftRenderer::TextureLookup(u32 texparam, u32 texpal, s16 s, s16 t, u16* color, u8* alpha)