From 59f7dedfb4e03690ef9228cce3874e424ef496f0 Mon Sep 17 00:00:00 2001
From: Magnus Norddahl <dpjudas@users.noreply.github.com>
Date: Wed, 16 Nov 2016 22:31:49 +0100
Subject: [PATCH] Added wall sprite support. Unfortunately it would seem that a
 bullet hole is not a wall sprite..

---
 src/r_poly.cpp            |  2 +-
 src/r_poly_sprite.h       |  2 +-
 src/r_poly_wallsprite.cpp | 96 ++++++++++++++++++++++++++++++++++++++-
 src/r_poly_wallsprite.h   |  2 +-
 4 files changed, 98 insertions(+), 4 deletions(-)

diff --git a/src/r_poly.cpp b/src/r_poly.cpp
index 179df248a..919b2ff78 100644
--- a/src/r_poly.cpp
+++ b/src/r_poly.cpp
@@ -183,7 +183,7 @@ void RenderPolyScene::RenderTranslucent()
 		else if ((obj.thing->renderflags & RF_SPRITETYPEMASK) == RF_WALLSPRITE)
 		{
 			RenderPolyWallSprite wallspr;
-			wallspr.Render(obj.thing, obj.sub, obj.subsectorDepth);
+			wallspr.Render(WorldToClip, obj.thing, obj.sub, obj.subsectorDepth);
 		}
 		else
 		{
diff --git a/src/r_poly_sprite.h b/src/r_poly_sprite.h
index d60710d04..085d9b570 100644
--- a/src/r_poly_sprite.h
+++ b/src/r_poly_sprite.h
@@ -30,8 +30,8 @@ public:
 	void Render(const TriMatrix &worldToClip, AActor *thing, subsector_t *sub, uint32_t subsectorDepth);
 
 	static bool IsThingCulled(AActor *thing);
+	static FTexture *GetSpriteTexture(AActor *thing, /*out*/ bool &flipX);
 
 private:
 	visstyle_t GetSpriteVisStyle(AActor *thing, double z);
-	FTexture *GetSpriteTexture(AActor *thing, /*out*/ bool &flipX);
 };
diff --git a/src/r_poly_wallsprite.cpp b/src/r_poly_wallsprite.cpp
index 86ddd52a9..63472e297 100644
--- a/src/r_poly_wallsprite.cpp
+++ b/src/r_poly_wallsprite.cpp
@@ -28,8 +28,102 @@
 #include "r_poly_wallsprite.h"
 #include "r_poly.h"
 
-void RenderPolyWallSprite::Render(AActor *thing, subsector_t *sub, uint32_t subsectorDepth)
+void RenderPolyWallSprite::Render(const TriMatrix &worldToClip, AActor *thing, subsector_t *sub, uint32_t subsectorDepth)
 {
 	if (RenderPolySprite::IsThingCulled(thing))
 		return;
+
+	DVector3 pos = thing->InterpolatedPosition(r_TicFracF);
+	pos.Z += thing->GetBobOffset(r_TicFracF);
+
+	bool flipTextureX = false;
+	FTexture *tex = RenderPolySprite::GetSpriteTexture(thing, flipTextureX);
+	if (tex == nullptr)
+		return;
+
+	DVector2 spriteScale = thing->Scale;
+	double thingxscalemul = spriteScale.X / tex->Scale.X;
+	double thingyscalemul = spriteScale.Y / tex->Scale.Y;
+	double spriteHeight = thingyscalemul * tex->GetHeight();
+
+	DAngle ang = thing->Angles.Yaw + 90;
+	double angcos = ang.Cos();
+	double angsin = ang.Sin();
+
+	// Determine left and right edges of sprite. The sprite's angle is its normal,
+	// so the edges are 90 degrees each side of it.
+	double x2 = tex->GetScaledWidth() * spriteScale.X;
+	double x1 = tex->GetScaledLeftOffset() * spriteScale.X;
+	DVector2 left, right;
+	left.X = pos.X - x1 * angcos;
+	left.Y = pos.Y - x1 * angsin;
+	right.X = left.X + x2 * angcos;
+	right.Y = right.Y + x2 * angsin;
+
+	//int scaled_to = tex->GetScaledTopOffset();
+	//int scaled_bo = scaled_to - tex->GetScaledHeight();
+	//gzt = pos.Z + scale.Y * scaled_to;
+	//gzb = pos.Z + scale.Y * scaled_bo;
+
+	DVector2 points[2] = { right, left };
+
+	TriVertex *vertices = PolyVertexBuffer::GetVertices(4);
+	if (!vertices)
+		return;
+
+	bool foggy = false;
+	int actualextralight = foggy ? 0 : extralight << 4;
+
+	std::pair<float, float> offsets[4] =
+	{
+		{ 0.0f,  1.0f },
+		{ 1.0f,  1.0f },
+		{ 1.0f,  0.0f },
+		{ 0.0f,  0.0f },
+	};
+
+	for (int i = 0; i < 4; i++)
+	{
+		auto &p = (i == 0 || i == 3) ? points[0] : points[1];
+
+		vertices[i].x = (float)p.X;
+		vertices[i].y = (float)p.Y;
+		vertices[i].z = (float)(pos.Z + spriteHeight * offsets[i].second);
+		vertices[i].w = 1.0f;
+		vertices[i].varying[0] = (float)(offsets[i].first * tex->Scale.X);
+		vertices[i].varying[1] = (float)((1.0f - offsets[i].second) * tex->Scale.Y);
+		if (flipTextureX)
+			vertices[i].varying[0] = 1.0f - vertices[i].varying[0];
+	}
+
+	bool fullbrightSprite = ((thing->renderflags & RF_FULLBRIGHT) || (thing->flags5 & MF5_BRIGHT));
+
+	TriUniforms uniforms;
+	uniforms.objectToClip = worldToClip;
+	if (fullbrightSprite || fixedlightlev >= 0 || fixedcolormap)
+	{
+		uniforms.light = 256;
+		uniforms.flags = TriUniforms::fixed_light;
+	}
+	else
+	{
+		uniforms.light = (uint32_t)((thing->Sector->lightlevel + actualextralight) / 255.0f * 256.0f);
+		uniforms.flags = 0;
+	}
+	uniforms.subsectorDepth = subsectorDepth;
+
+	PolyDrawArgs args;
+	args.uniforms = uniforms;
+	args.vinput = vertices;
+	args.vcount = 4;
+	args.mode = TriangleDrawMode::Fan;
+	args.ccw = true;
+	args.clipleft = 0;
+	args.cliptop = 0;
+	args.clipright = viewwidth;
+	args.clipbottom = viewheight;
+	args.stenciltestvalue = 0;
+	args.stencilwritevalue = 1;
+	args.SetTexture(tex);
+	PolyTriangleDrawer::draw(args, TriDrawVariant::DrawSubsector);
 }
diff --git a/src/r_poly_wallsprite.h b/src/r_poly_wallsprite.h
index ce6917e58..dd4ba28da 100644
--- a/src/r_poly_wallsprite.h
+++ b/src/r_poly_wallsprite.h
@@ -27,5 +27,5 @@
 class RenderPolyWallSprite
 {
 public:
-	void Render(AActor *thing, subsector_t *sub, uint32_t subsectorDepth);
+	void Render(const TriMatrix &worldToClip, AActor *thing, subsector_t *sub, uint32_t subsectorDepth);
 };