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, 5 insertions, 66 deletions

diff --git a/src/GPU2D_Soft.cpp b/src/GPU2D_Soft.cpp
index 9e7d849..6d0252c 100644
--- a/src/GPU2D_Soft.cpp
+++ b/src/GPU2D_Soft.cpp
@@ -27,68 +27,7 @@ namespace GPU2D
 SoftRenderer::SoftRenderer(melonDS::GPU& gpu)
     : Renderer2D(), GPU(gpu)
 {
-    // initialize mosaic table
-    for (int m = 0; m < 16; m++)
-    {
-        for (int x = 0; x < 256; x++)
-        {
-            int offset = x % (m+1);
-            MosaicTable[m][x] = offset;
-        }
-    }
-}
-
-u32 SoftRenderer::ColorBlend4(u32 val1, u32 val2, u32 eva, u32 evb)
-{
-    u32 r =  (((val1 & 0x00003F) * eva) + ((val2 & 0x00003F) * evb) + 0x000008) >> 4;
-    u32 g = ((((val1 & 0x003F00) * eva) + ((val2 & 0x003F00) * evb) + 0x000800) >> 4) & 0x007F00;
-    u32 b = ((((val1 & 0x3F0000) * eva) + ((val2 & 0x3F0000) * evb) + 0x080000) >> 4) & 0x7F0000;
-
-    if (r > 0x00003F) r = 0x00003F;
-    if (g > 0x003F00) g = 0x003F00;
-    if (b > 0x3F0000) b = 0x3F0000;
-
-    return r | g | b | 0xFF000000;
-}
-
-u32 SoftRenderer::ColorBlend5(u32 val1, u32 val2)
-{
-    u32 eva = ((val1 >> 24) & 0x1F) + 1;
-    u32 evb = 32 - eva;
-
-    if (eva == 32) return val1;
-
-    u32 r =  (((val1 & 0x00003F) * eva) + ((val2 & 0x00003F) * evb) + 0x000010) >> 5;
-    u32 g = ((((val1 & 0x003F00) * eva) + ((val2 & 0x003F00) * evb) + 0x001000) >> 5) & 0x007F00;
-    u32 b = ((((val1 & 0x3F0000) * eva) + ((val2 & 0x3F0000) * evb) + 0x100000) >> 5) & 0x7F0000;
-
-    if (r > 0x00003F) r = 0x00003F;
-    if (g > 0x003F00) g = 0x003F00;
-    if (b > 0x3F0000) b = 0x3F0000;
-
-    return r | g | b | 0xFF000000;
-}
-
-u32 SoftRenderer::ColorBrightnessUp(u32 val, u32 factor, u32 bias)
-{
-    u32 rb = val & 0x3F003F;
-    u32 g = val & 0x003F00;
-
-    rb += (((((0x3F003F - rb) * factor) + (bias*0x010001)) >> 4) & 0x3F003F);
-    g +=  (((((0x003F00 - g ) * factor) + (bias*0x000100)) >> 4) & 0x003F00);
-
-    return rb | g | 0xFF000000;
-}
-
-u32 SoftRenderer::ColorBrightnessDown(u32 val, u32 factor, u32 bias)
-{
-    u32 rb = val & 0x3F003F;
-    u32 g = val & 0x003F00;
-
-    rb -= ((((rb * factor) + (bias*0x010001)) >> 4) & 0x3F003F);
-    g -=  ((((g  * factor) + (bias*0x000100)) >> 4) & 0x003F00);
-
-    return rb | g | 0xFF000000;
+    // mosaic table is initialized at compile-time
 }
 
 u32 SoftRenderer::ColorComposite(int i, u32 val1, u32 val2)
@@ -365,11 +304,11 @@ void SoftRenderer::DrawScanline(u32 line, Unit* unit)
 void SoftRenderer::VBlankEnd(Unit* unitA, Unit* unitB)
 {
 #ifdef OGLRENDERER_ENABLED
-    if (GPU.GPU3D.IsRendererAccelerated())
+    if (Renderer3D& renderer3d = GPU.GPU3D.GetCurrentRenderer(); renderer3d.Accelerated)
     {
         if ((unitA->CaptureCnt & (1<<31)) && (((unitA->CaptureCnt >> 29) & 0x3) != 1))
         {
-            reinterpret_cast<GLRenderer*>(GPU.GPU3D.GetCurrentRenderer())->PrepareCaptureFrame();
+            renderer3d.PrepareCaptureFrame();
         }
     }
 #endif
@@ -779,7 +718,7 @@ void SoftRenderer::DrawScanline_BGOBJ(u32 line)
         memset(WindowMask, 0xFF, 256);
 
     ApplySpriteMosaicX();
-    CurBGXMosaicTable = MosaicTable[CurUnit->BGMosaicSize[0]];
+    CurBGXMosaicTable = MosaicTable[CurUnit->BGMosaicSize[0]].data();
 
     switch (CurUnit->DispCnt & 0x7)
     {
@@ -1564,7 +1503,7 @@ void SoftRenderer::ApplySpriteMosaicX()
 
     u32* objLine = OBJLine[CurUnit->Num];
 
-    u8* curOBJXMosaicTable = MosaicTable[CurUnit->OBJMosaicSize[1]];
+    u8* curOBJXMosaicTable = MosaicTable[CurUnit->OBJMosaicSize[1]].data();
 
     u32 lastcolor = objLine[0];