Sprinkle `const` around where appropriate (#1909)

* Sprinkle `const` around where appropriate

- This will make it easier to use `NDS` objects in `const` contexts (e.g. `const` parameters or methods)

* Remove the `const` qualifier on `DSi_DSP::DSPRead16`

- MMIO reads can be non-pure, so this may not be `const` in the future

1 files changed, 7 insertions, 7 deletions

diff --git a/src/GPU3D_Soft.cpp b/src/GPU3D_Soft.cpp
index 03c6265..894ac94 100644
--- a/src/GPU3D_Soft.cpp
+++ b/src/GPU3D_Soft.cpp
@@ -112,7 +112,7 @@ void SoftRenderer::SetThreaded(bool threaded) noexcept
     }
 }
 
-void SoftRenderer::TextureLookup(u32 texparam, u32 texpal, s16 s, s16 t, u16* color, u8* alpha)
+void SoftRenderer::TextureLookup(u32 texparam, u32 texpal, s16 s, s16 t, u16* color, u8* alpha) const
 {
     u32 vramaddr = (texparam & 0xFFFF) << 3;
 
@@ -388,7 +388,7 @@ bool DepthTest_LessThan_FrontFacing(s32 dstz, s32 z, u32 dstattr)
     return false;
 }
 
-u32 SoftRenderer::AlphaBlend(u32 srccolor, u32 dstcolor, u32 alpha) noexcept
+u32 SoftRenderer::AlphaBlend(u32 srccolor, u32 dstcolor, u32 alpha) const noexcept
 {
     u32 dstalpha = dstcolor >> 24;
 
@@ -418,7 +418,7 @@ u32 SoftRenderer::AlphaBlend(u32 srccolor, u32 dstcolor, u32 alpha) noexcept
     return srcR | (srcG << 8) | (srcB << 16) | (dstalpha << 24);
 }
 
-u32 SoftRenderer::RenderPixel(Polygon* polygon, u8 vr, u8 vg, u8 vb, s16 s, s16 t)
+u32 SoftRenderer::RenderPixel(const Polygon* polygon, u8 vr, u8 vg, u8 vb, s16 s, s16 t) const
 {
     u8 r, g, b, a;
 
@@ -565,7 +565,7 @@ void SoftRenderer::PlotTranslucentPixel(u32 pixeladdr, u32 color, u32 z, u32 pol
     AttrBuffer[pixeladdr] = attr;
 }
 
-void SoftRenderer::SetupPolygonLeftEdge(SoftRenderer::RendererPolygon* rp, s32 y)
+void SoftRenderer::SetupPolygonLeftEdge(SoftRenderer::RendererPolygon* rp, s32 y) const
 {
     Polygon* polygon = rp->PolyData;
 
@@ -592,7 +592,7 @@ void SoftRenderer::SetupPolygonLeftEdge(SoftRenderer::RendererPolygon* rp, s32 y
                               polygon->FinalW[rp->CurVL], polygon->FinalW[rp->NextVL], y);
 }
 
-void SoftRenderer::SetupPolygonRightEdge(SoftRenderer::RendererPolygon* rp, s32 y)
+void SoftRenderer::SetupPolygonRightEdge(SoftRenderer::RendererPolygon* rp, s32 y) const
 {
     Polygon* polygon = rp->PolyData;
 
@@ -619,7 +619,7 @@ void SoftRenderer::SetupPolygonRightEdge(SoftRenderer::RendererPolygon* rp, s32
                               polygon->FinalW[rp->CurVR], polygon->FinalW[rp->NextVR], y);
 }
 
-void SoftRenderer::SetupPolygon(SoftRenderer::RendererPolygon* rp, Polygon* polygon)
+void SoftRenderer::SetupPolygon(SoftRenderer::RendererPolygon* rp, Polygon* polygon) const
 {
     u32 nverts = polygon->NumVertices;
 
@@ -1375,7 +1375,7 @@ void SoftRenderer::RenderScanline(s32 y, int npolys)
     }
 }
 
-u32 SoftRenderer::CalculateFogDensity(u32 pixeladdr)
+u32 SoftRenderer::CalculateFogDensity(u32 pixeladdr) const
 {
     u32 z = DepthBuffer[pixeladdr];
     u32 densityid, densityfrac;