From ba68bc128e27d75b524d926033597f698ce28bb6 Mon Sep 17 00:00:00 2001
From: Nico de Poel <ndepoel@gmail.com>
Date: Sun, 15 Jan 2023 17:15:34 +0100
Subject: [PATCH] Write face vertex indices to output file instead of triangle
 data, which takes up less space and allows the PS1 code to decide how to draw
 the primitives.

---
 main.cpp | 16 +++++++---------
 ps1bsp.h |  9 +++------
 2 files changed, 10 insertions(+), 15 deletions(-)

diff --git a/main.cpp b/main.cpp
index fc5a7cd..8667249 100644
--- a/main.cpp
+++ b/main.cpp
@@ -211,6 +211,9 @@ int process_faces(const world_t* world)
 	{
 		face_t* face = &world->faces[faceIdx];
 
+		ps1bsp_face_t outFace = { 0 };
+		outFace.firstVertexIndex = faceVertIndices.size();
+
 		// Traverse the list of face edges to collect all of the face's vertices
 		for (int edgeListIdx = 0; edgeListIdx < face->ledge_num; ++edgeListIdx)
 		{
@@ -223,9 +226,6 @@ int process_faces(const world_t* world)
 			faceVertIndices.push_back(vertIndex);
 		}
 
-		ps1bsp_face_t outFace = { 0 };
-		outFace.firstTriangleId = outTriangles.size();
-
 		//printf("Face %d: %d vertices\n", faceIdx, faceVerts.size());
 
 		// Triangulate face into polygons (triangle fan, the naive method)
@@ -240,19 +240,17 @@ int process_faces(const world_t* world)
 			outTriangles.push_back(outTriangle);
 		}
 
-		outFace.numTriangles = outTriangles.size() - outFace.firstTriangleId;
+		outFace.numVertices = faceVertIndices.size() - outFace.firstVertexIndex;
 		outFaces.push_back(outFace);
-
-		faceVertIndices.clear();
 	}
 
 	// Write triangle and face data to file
-	fwrite(outTriangles.data(), sizeof(ps1bsp_triangle_t), outTriangles.size(), fbsp);
+	fwrite(faceVertIndices.data(), sizeof(unsigned short), faceVertIndices.size(), fbsp);
 	fwrite(outFaces.data(), sizeof(ps1bsp_face_t), outFaces.size(), fbsp);
 
 	// Update header information
 	outHeader.numVertices = world->numVertices;
-	outHeader.numTriangles = outTriangles.size();
+	outHeader.numFaceVertIndices = faceVertIndices.size();
 	outHeader.numFaces = outFaces.size();
 
 	// Write final header
@@ -260,7 +258,7 @@ int process_faces(const world_t* world)
 	fwrite(&outHeader, sizeof(ps1bsp_header_t), 1, fbsp);
 	fclose(fbsp);
 
-	printf("PS1BSP: wrote %d vertices, %d triangles, %d faces\n", outHeader.numVertices, outHeader.numTriangles, outHeader.numFaces);
+	printf("PS1BSP: wrote %d vertices, %d indices, %d faces\n", outHeader.numVertices, outHeader.numFaceVertIndices, outHeader.numFaces);
 
 	return 1;
 }
diff --git a/ps1bsp.h b/ps1bsp.h
index 34490e9..eafbc55 100644
--- a/ps1bsp.h
+++ b/ps1bsp.h
@@ -22,7 +22,7 @@ Probable rendering process:
 typedef struct
 {
 	unsigned short numVertices;
-	unsigned short numTriangles;
+	unsigned short numFaceVertIndices;
 	unsigned short numFaces;
 } ps1bsp_header_t;
 
@@ -62,11 +62,8 @@ typedef struct
 
 typedef struct
 {
-	unsigned short firstTriangleId;	// TODO: could also just do first-index, num-indices here. No real need for a triangle_t struct.
-	unsigned short numTriangles;
-
-	unsigned short firstQuadId;		// For if/when we decide to add quads to the mix
-	unsigned short numQuads;
+	unsigned short firstVertexIndex;
+	unsigned short numVertices;
 } ps1bsp_face_t;
 
 // Pre-parsed and encoded entity data (this runs the risk of becoming too bloated)