From ce6e1e1e472e3b6cef3892007aa6f1170d0f9aec Mon Sep 17 00:00:00 2001
From: Magnus Norddahl <dpjudas@users.noreply.github.com>
Date: Fri, 2 Dec 2016 13:24:53 +0100
Subject: [PATCH] Fully hook up sprite clipping by subsector

---
 src/r_poly_portal.cpp | 17 ++++-------------
 src/r_poly_sprite.cpp | 20 +++++++++++++-------
 src/r_poly_sprite.h   |  2 +-
 3 files changed, 18 insertions(+), 21 deletions(-)

diff --git a/src/r_poly_portal.cpp b/src/r_poly_portal.cpp
index 7d8c385dd..1047164cb 100644
--- a/src/r_poly_portal.cpp
+++ b/src/r_poly_portal.cpp
@@ -150,18 +150,9 @@ void RenderPolyPortal::RenderSprite(AActor *thing, double sortDistance, DVector2
 			DVector2 mid = left * (1.0 - t) + right * t;
 			double tmid = t1 * (1.0 - t) + t2 * t;
 			
-			if (sideLeft == 0)
-			{
-				RenderSprite(thing, sortDistance, mid, right, tmid, t2, bsp->children[sideRight]);
-				right = mid;
-				t2 = tmid;
-			}
-			else
-			{
-				RenderSprite(thing, sortDistance, left, mid, t1, tmid, bsp->children[sideRight]);
-				left = mid;
-				t1 = tmid;
-			}
+			RenderSprite(thing, sortDistance, mid, right, tmid, t2, bsp->children[sideRight]);
+			right = mid;
+			t2 = tmid;
 		}
 		node = bsp->children[sideLeft];
 	}
@@ -346,7 +337,7 @@ void RenderPolyPortal::RenderTranslucent(int portalDepth)
 		else
 		{
 			RenderPolySprite spr;
-			spr.Render(WorldToClip, PortalPlane, obj.thing, obj.sub, obj.subsectorDepth, StencilValue + 1);
+			spr.Render(WorldToClip, PortalPlane, obj.thing, obj.sub, obj.subsectorDepth, StencilValue + 1, obj.SpriteLeft, obj.SpriteRight);
 		}
 	}
 }
diff --git a/src/r_poly_sprite.cpp b/src/r_poly_sprite.cpp
index 5d4a9ba6c..c17bc5909 100644
--- a/src/r_poly_sprite.cpp
+++ b/src/r_poly_sprite.cpp
@@ -63,10 +63,10 @@ bool RenderPolySprite::GetLine(AActor *thing, DVector2 &left, DVector2 &right)
 	return true;
 }
 
-void RenderPolySprite::Render(const TriMatrix &worldToClip, const Vec4f &clipPlane, AActor *thing, subsector_t *sub, uint32_t subsectorDepth, uint32_t stencilValue)
+void RenderPolySprite::Render(const TriMatrix &worldToClip, const Vec4f &clipPlane, AActor *thing, subsector_t *sub, uint32_t subsectorDepth, uint32_t stencilValue, float t1, float t2)
 {
-	DVector2 points[2];
-	if (!GetLine(thing, points[0], points[1]))
+	DVector2 line[2];
+	if (!GetLine(thing, line[0], line[1]))
 		return;
 	
 	DVector3 pos = thing->InterpolatedPosition(r_TicFracF);
@@ -108,10 +108,16 @@ void RenderPolySprite::Render(const TriMatrix &worldToClip, const Vec4f &clipPla
 
 	std::pair<float, float> offsets[4] =
 	{
-		{ 0.0f,  1.0f },
-		{ 1.0f,  1.0f },
-		{ 1.0f,  0.0f },
-		{ 0.0f,  0.0f },
+		{ t1,  1.0f },
+		{ t2,  1.0f },
+		{ t2,  0.0f },
+		{ t1,  0.0f },
+	};
+
+	DVector2 points[2] =
+	{
+		line[0] * (1.0 - t1) + line[1] * t1,
+		line[0] * (1.0 - t2) + line[1] * t2
 	};
 
 	for (int i = 0; i < 4; i++)
diff --git a/src/r_poly_sprite.h b/src/r_poly_sprite.h
index 8ce9caffd..085845e50 100644
--- a/src/r_poly_sprite.h
+++ b/src/r_poly_sprite.h
@@ -29,7 +29,7 @@ class Vec4f;
 class RenderPolySprite
 {
 public:
-	void Render(const TriMatrix &worldToClip, const Vec4f &clipPlane, AActor *thing, subsector_t *sub, uint32_t subsectorDepth, uint32_t stencilValue);
+	void Render(const TriMatrix &worldToClip, const Vec4f &clipPlane, AActor *thing, subsector_t *sub, uint32_t subsectorDepth, uint32_t stencilValue, float t1, float t2);
 
 	static bool GetLine(AActor *thing, DVector2 &left, DVector2 &right);
 	static bool IsThingCulled(AActor *thing);