Reorganized the model rendering loop to reduce duplicate calculations and condition checks.

main.c

@@ -293,9 +293,18 @@ static int fakeLight(const int *norm)
 
 void drawModel(ps1mdl_t *model, TIM_IMAGE *frontTex, TIM_IMAGE *backTex, int xOffset, int frameCounter)
 {
+	TIM_IMAGE *tex;
+	short u0, u1, u2, uoffs, voffs;
+
 	int frameNum = frameCounter % model->header->frameCount;
 	int vertOffs = frameNum * model->header->vertexCount;
 
+	unsigned short halfSkinWidth = model->header->skinWidth >> 1;
+	short frontUOffs = (frontTex->prect->x % 64) << (2 - (frontTex->mode & 0x3));
+	short frontVOffs = (frontTex->prect->y & 0xFF);
+	short backUOffs = (backTex->prect->x % 64) << (2 - (backTex->mode & 0x3));
+	short backVOffs = (backTex->prect->y & 0xFF);
+
 	for (int triIdx = 0; triIdx < model->header->triangleCount; ++triIdx)
 	{
 		ps1mdl_triangle_t *tri = &model->triangles[triIdx];
@@ -318,15 +327,19 @@ void drawModel(ps1mdl_t *model, TIM_IMAGE *frontTex, TIM_IMAGE *backTex, int xOf
 		int lit1 = fakeLight(anorms[v1->normalIndex]);
 		int lit2 = fakeLight(anorms[v2->normalIndex]);
 
-		// Since we have the texture split into two parts, we need to correct the UVs that are *not* on the seam, instead of the other way round
-		short u0 = !tri->frontFace && !tc0->onSeam ? tc0->u - (model->header->skinWidth >> 1) : tc0->u;
-		short u1 = !tri->frontFace && !tc1->onSeam ? tc1->u - (model->header->skinWidth >> 1) : tc1->u;
-		short u2 = !tri->frontFace && !tc2->onSeam ? tc2->u - (model->header->skinWidth >> 1) : tc2->u;
-
-		TIM_IMAGE *tex = tri->frontFace ? frontTex : backTex;
-
-		short uoffs = (tex->prect->x % 64) << (2 - (tex->mode & 0x3));
-		short voffs = (tex->prect->y & 0xFF);
+		if (tri->frontFace)
+		{
+			u0 = tc0->u, u1 = tc1->u, u2 = tc2->u;
+			tex = frontTex, uoffs = frontUOffs, voffs = frontVOffs;
+		}
+		else
+		{
+			// Since we have the texture split into two parts, we need to correct the UVs that are *not* on the seam, instead of the other way round
+			u0 = tc0->onSeam ? tc0->u : tc0->u - halfSkinWidth;
+			u1 = tc1->onSeam ? tc1->u : tc1->u - halfSkinWidth;
+			u2 = tc2->onSeam ? tc2->u : tc2->u - halfSkinWidth;
+			tex = backTex, uoffs = backUOffs, voffs = backVOffs;
+		}
 
 		POLY_GT3 *poly = (POLY_GT3*)nextpri;
 		setPolyGT3(poly);