From 35c2d6d14eda71dc86dca5736e30a85e7ffcf4b7 Mon Sep 17 00:00:00 2001
From: Christoph Oelckers <coelckers@users.noreply.github.com>
Date: Sun, 28 Nov 2021 18:05:19 +0100
Subject: [PATCH] - fixed translucent voxel rendering.

---
 source/build/src/polymost.cpp              | 23 ++++++++++++++++++++++
 source/core/rendering/scene/hw_sprites.cpp |  7 ++++---
 2 files changed, 27 insertions(+), 3 deletions(-)

diff --git a/source/build/src/polymost.cpp b/source/build/src/polymost.cpp
index 907ac7fca..bf7911b24 100644
--- a/source/build/src/polymost.cpp
+++ b/source/build/src/polymost.cpp
@@ -3927,6 +3927,29 @@ int32_t polymost_voxdraw(voxmodel_t* m, tspriteptr_t const tspr, bool rotate)
     auto tex = TexMan.GetGameTexture(m->model->GetPaletteTexture());
     GLInterface.SetTexture(tex, TRANSLATION(Translation_Remap + curbasepal, globalpal), CLAMP_NOFILTER_XY, true);
     GLInterface.SetModel(m->model, 0, 0, 0);
+
+    // The shade rgb from the tint is ignored here.
+    pc[0] = (float)globalr * (1.f / 255.f);
+    pc[1] = (float)globalg * (1.f / 255.f);
+    pc[2] = (float)globalb * (1.f / 255.f);
+
+    bool trans = (tspr->cstat & CSTAT_SPRITE_TRANSLUCENT);
+    float alpha;
+    FRenderStyle RenderStyle;
+    if (trans)
+    {
+        RenderStyle = GetRenderStyle(0, !!(tspr->cstat & CSTAT_SPRITE_TRANSLUCENT_INVERT));
+        alpha = GetAlphaFromBlend((tspr->cstat & CSTAT_SPRITE_TRANSLUCENT_INVERT) ? DAMETH_TRANS2 : DAMETH_TRANS1, 0);
+    }
+    else
+    {
+        RenderStyle = LegacyRenderStyles[STYLE_Translucent];
+        alpha = 1.f;
+    }
+    alpha *= 1.f - spriteext[tspr->owner].alpha;
+    GLInterface.SetRenderStyle(RenderStyle);
+    GLInterface.SetColor(pc[0], pc[1], pc[2], alpha);
+
     GLInterface.Draw(DT_Triangles, 0, 0);
     GLInterface.SetModel(nullptr, 0, 0, 0);
     GLInterface.SetCull(Cull_None);
diff --git a/source/core/rendering/scene/hw_sprites.cpp b/source/core/rendering/scene/hw_sprites.cpp
index ee9882455..3082bc274 100644
--- a/source/core/rendering/scene/hw_sprites.cpp
+++ b/source/core/rendering/scene/hw_sprites.cpp
@@ -144,17 +144,19 @@ void HWSprite::DrawSprite(HWDrawInfo* di, FRenderState& state, bool translucent)
 	}
 	else
 	{
-		state.EnableModelMatrix(true);
-		state.mModelMatrix = rotmat;
 		FHWModelRenderer mr(state, dynlightindex);
 		if (modelframe < 0)
 		{
+			state.mModelMatrix = rotmat;
+
 			auto model = voxel->model;
 			state.SetDepthFunc(DF_LEqual);
 			state.EnableTexture(true);
 			model->BuildVertexBuffer(&mr);
+			mr.BeginDrawModel(RenderStyle, nullptr, rotmat, portalState.isMirrored());
 			mr.SetupFrame(model, 0, 0, 0);
 			model->RenderFrame(&mr, TexMan.GetGameTexture(model->GetPaletteTexture()), 0, 0, 0.f, TRANSLATION(Translation_Remap + curbasepal, palette));
+			mr.EndDrawModel(RenderStyle, nullptr);
 			state.SetDepthFunc(DF_Less);
 			state.SetVertexBuffer(screen->mVertexData);
 
@@ -165,7 +167,6 @@ void HWSprite::DrawSprite(HWDrawInfo* di, FRenderState& state, bool translucent)
 		}
 		state.SetObjectColor(0xffffffff);
 		state.SetVertexBuffer(screen->mVertexData);
-		state.EnableModelMatrix(false);
 	}
 
 	if (translucent)