From cba2374abd35e77055bff817c282d8975be48b9d Mon Sep 17 00:00:00 2001
From: "Unknown W. Brackets" <checkins@unknownbrackets.org>
Date: Mon, 3 Jan 2022 22:56:26 -0800
Subject: [PATCH] softgpu: Separate calculation of S/T.

We could probably reuse, but we're not right now and it complicates the
logic.
---
 GPU/Software/Lighting.cpp      | 36 +++++++++++++++-------------------
 GPU/Software/Lighting.h        |  3 ++-
 GPU/Software/TransformUnit.cpp |  5 ++++-
 3 files changed, 22 insertions(+), 22 deletions(-)

diff --git a/GPU/Software/Lighting.cpp b/GPU/Software/Lighting.cpp
index d4d7a020ee..35a1dde62a 100644
--- a/GPU/Software/Lighting.cpp
+++ b/GPU/Software/Lighting.cpp
@@ -43,6 +43,22 @@ static inline float pspLightPow(float v, float e) {
 	return v;
 }
 
+static inline float GenerateLightCoord(VertexData &vertex, int light) {
+	// TODO: Should specular lighting should affect this, too?  Doesn't in GLES.
+	Vec3<float> L = GetLightVec(gstate.lpos, light);
+	// In other words, L.Length2() == 0.0f means Dot({0, 0, 1}, worldnormal).
+	float diffuse_factor = Dot(L.NormalizedOr001(cpu_info.bSSE4_1), vertex.worldnormal);
+
+	return (diffuse_factor + 1.0f) / 2.0f;
+}
+
+void GenerateLightST(VertexData &vertex) {
+	// Always calculate texture coords from lighting results if environment mapping is active
+	// This should be done even if lighting is disabled altogether.
+	vertex.texturecoords.s() = GenerateLightCoord(vertex, gstate.getUVLS0());
+	vertex.texturecoords.t() = GenerateLightCoord(vertex, gstate.getUVLS1());
+}
+
 void Process(VertexData& vertex, bool hasColor) {
 	const int materialupdate = gstate.materialupdate & (hasColor ? 7 : 0);
 
@@ -53,26 +69,6 @@ void Process(VertexData& vertex, bool hasColor) {
 	Vec3<float> final_color = mec + mac * Vec3<float>::FromRGB(gstate.getAmbientRGBA());
 	Vec3<float> specular_color(0.0f, 0.0f, 0.0f);
 
-	for (unsigned int light = 0; light < 4; ++light) {
-		// Always calculate texture coords from lighting results if environment mapping is active
-		// TODO: Should specular lighting should affect this, too?  Doesn't in GLES.
-		// This should be done even if lighting is disabled altogether.
-		if (gstate.getUVGenMode() == GE_TEXMAP_ENVIRONMENT_MAP) {
-			Vec3<float> L = GetLightVec(gstate.lpos, light);
-			// In other words, L.Length2() == 0.0f means Dot({0, 0, 1}, worldnormal).
-			float diffuse_factor = Dot(L.NormalizedOr001(cpu_info.bSSE4_1), vertex.worldnormal);
-
-			if (gstate.getUVLS0() == (int)light)
-				vertex.texturecoords.s() = (diffuse_factor + 1.f) / 2.f;
-
-			if (gstate.getUVLS1() == (int)light)
-				vertex.texturecoords.t() = (diffuse_factor + 1.f) / 2.f;
-		}
-	}
-
-	if (!gstate.isLightingEnabled())
-		return;
-
 	for (unsigned int light = 0; light < 4; ++light) {
 		if (!gstate.isLightChanEnabled(light))
 			continue;
diff --git a/GPU/Software/Lighting.h b/GPU/Software/Lighting.h
index 9e08eacade..e5915e6aac 100644
--- a/GPU/Software/Lighting.h
+++ b/GPU/Software/Lighting.h
@@ -21,6 +21,7 @@
 
 namespace Lighting {
 
+void GenerateLightST(VertexData &vertex);
 void Process(VertexData& vertex, bool hasColor);
 
-}
\ No newline at end of file
+}
diff --git a/GPU/Software/TransformUnit.cpp b/GPU/Software/TransformUnit.cpp
index bdecb90372..b15bb0115c 100644
--- a/GPU/Software/TransformUnit.cpp
+++ b/GPU/Software/TransformUnit.cpp
@@ -277,10 +277,13 @@ VertexData TransformUnit::ReadVertex(VertexReader &vreader, bool &outside_range_
 			Vec3<float> stq = tgen * source + Vec3<float>(gstate.tgenMatrix[9], gstate.tgenMatrix[10], gstate.tgenMatrix[11]);
 			float z_recip = 1.0f / stq.z;
 			vertex.texturecoords = Vec2f(stq.x * z_recip, stq.y * z_recip);
+		} else if (gstate.getUVGenMode() == GE_TEXMAP_ENVIRONMENT_MAP) {
+			Lighting::GenerateLightST(vertex);
 		}
 
 		PROFILE_THIS_SCOPE("light");
-		Lighting::Process(vertex, vreader.hasColor0());
+		if (gstate.isLightingEnabled())
+			Lighting::Process(vertex, vreader.hasColor0());
 	} else {
 		vertex.screenpos.x = (int)(pos[0] * 16) + gstate.getOffsetX16();
 		vertex.screenpos.y = (int)(pos[1] * 16) + gstate.getOffsetY16();