Rewrote model rendering code using GTE acceleration. Now with 100% more perspective!

main.c

@@ -31,7 +31,7 @@
 #define SCREENHEIGHT	240
 
 #define NUMVERTEXNORMALS	162
-static int anorms[NUMVERTEXNORMALS][3] = {
+static short anorms[NUMVERTEXNORMALS][3] = {
 #include "ps1anorms.h"
 };
 
@@ -78,6 +78,21 @@ typedef struct
 ps1mdl_t playerModel, shamblerModel;
 ps1skin_t playerSkin, shamblerSkin;
 
+SVECTOR rot = { 0 };
+VECTOR pos = { -200, 128, 64 };
+
+MATRIX color_mtx = {
+	ONE, 0, 0,
+	ONE, 0, 0,
+	ONE, 0, 0
+};
+
+MATRIX light_mtx = {
+	ONE, 0, 0,
+	0, 0, 0,
+	0, 0, 0
+};
+
 void loadModel(const u_long* data, ps1mdl_t *mdl)
 {
 	const char *bytes = (const char*)data;
@@ -168,6 +183,10 @@ void init(void)
 	loadModel(mdl_shambler, &shamblerModel);
 	loadSkin(tim_shambler_f, tim_shambler_b, &shamblerSkin);
 
+	InitGeom();
+	gte_SetGeomOffset(SCREENWIDTH >> 1, SCREENHEIGHT >> 1);
+	gte_SetGeomScreen(SCREENWIDTH >> 1);	// Screen depth for FOV control
+
 	// Set texture page for the entire drawing environment. Nice in some cases perhaps, but not what we need.
 	//draw[0].tpage = getTPage(playerFrontTex.mode & 0x3, 0, playerFrontTex.prect->x, playerFrontTex.prect->y);
 	//draw[1].tpage = getTPage(playerFrontTex.mode & 0x3, 0, playerFrontTex.prect->x, playerFrontTex.prect->y);
@@ -326,10 +345,13 @@ static int fakeLight(const int *norm)
 	return lit;
 }
 
+SVECTOR outPos;
+
 void drawModel(ps1mdl_t *model, ps1skin_t *skin, int xOffset, int frameCounter)
 {
 	ps1texture_t *tex;
 	short u0, u1, u2, uoffs, voffs;
+	int p;
 
 	int frameNum = frameCounter % model->header->frameCount;
 	int vertOffs = frameNum * model->header->vertexCount;
@@ -343,20 +365,31 @@ void drawModel(ps1mdl_t *model, ps1skin_t *skin, int xOffset, int frameCounter)
 		ps1mdl_vertex_t *v1 = &model->vertices[tri->vertexIndex[1] + vertOffs];
 		ps1mdl_vertex_t *v2 = &model->vertices[tri->vertexIndex[2] + vertOffs];
 
-		// Normally you'd have GTE do this but we're just going for a quick hack now
-		unsigned short depth = ((unsigned short)v0->position[1] + (unsigned short)v1->position[1] + (unsigned short)v2->position[1]) / 3;
-		if (depth >= OTLEN)
+		// Swizzle the coordinates because Quake Z is up
+		SVECTOR pos0 = { v0->position[0], -v0->position[2], v0->position[1] };
+		SVECTOR pos1 = { v1->position[0], -v1->position[2], v1->position[1] };
+		SVECTOR pos2 = { v2->position[0], -v2->position[2], v2->position[1] };
+
+		gte_ldv3(&pos0, &pos1, &pos2);
+		gte_rtpt();	// Rotation, Translation and Perspective triplet (all three vertices at once)
+
+		// Normal clipping for backface culling
+		gte_nclip();
+		gte_stopz(&p);
+		if (p < 0)
+			continue;
+
+		// Average Z for depth sorting
+		gte_avsz3();
+		gte_stotz(&p);
+		unsigned short depth = p;//p >> 2;
+		if (depth < 0 || depth >= OTLEN)
 			continue;
 
 		ps1mdl_texcoord_t *tc0 = &model->texCoords[tri->vertexIndex[0]];
 		ps1mdl_texcoord_t *tc1 = &model->texCoords[tri->vertexIndex[1]];
 		ps1mdl_texcoord_t *tc2 = &model->texCoords[tri->vertexIndex[2]];
 
-		// Calculate some Lambert shading based on a static light vector
-		int lit0 = fakeLight(anorms[v0->normalIndex]);
-		int lit1 = fakeLight(anorms[v1->normalIndex]);
-		int lit2 = fakeLight(anorms[v2->normalIndex]);
-
 		if (tri->frontFace)
 		{
 			u0 = tc0->u, u1 = tc1->u, u2 = tc2->u;
@@ -375,11 +408,25 @@ void drawModel(ps1mdl_t *model, ps1skin_t *skin, int xOffset, int frameCounter)
 
 		POLY_GT3 *poly = (POLY_GT3*)nextpri;
 		setPolyGT3(poly);
-		setXY3(poly, xOffset + v0->position[0], 240 - v0->position[2], xOffset + v1->position[0], 240 - v1->position[2], xOffset + v2->position[0], 240 - v2->position[2]);
+
+		// Store transformed vertex coordinates in screen space
+		gte_stsxy0(&poly->x0);
+		gte_stsxy1(&poly->x1);
+		gte_stsxy2(&poly->x2);
+
+		// Copy some values for on-screen debugging
+		outPos.vx = poly->x0;
+		outPos.vy = poly->y0;
+		outPos.vz = p;
+
+		// Calculate vertex color based on normal
+		gte_ldrgb(&poly->r0);
+		gte_ldv3(anorms[v0->normalIndex], anorms[v1->normalIndex], anorms[v2->normalIndex]);
+		gte_nct();
+		gte_strgb3(&poly->r0, &poly->r1, &poly->r2);
+
+		// Set texture parameters
 		setUV3(poly, uoffs + u0, voffs + tc0->v, uoffs + u1, voffs + tc1->v, uoffs + u2, voffs + tc2->v);
-		setRGB0(poly, lit0, lit0, lit0);
-		setRGB1(poly, lit1, lit1, lit1);
-		setRGB2(poly, lit2, lit2, lit2);
 		setClut(poly, tex->crect.x, tex->crect.y);
 		setTPage(poly, tex->mode & 0x3, 0, tex->prect.x, tex->prect.y);
 
@@ -392,30 +439,28 @@ void drawStuff(int counter)
 {
 	ClearOTagR(ot[db], OTLEN);
 
-	// Print the obligatory hello world and counter to show that the
-	// program isn't locking up to the last created text stream
-	FntPrint(-1, "COUNTER=%d, SIN=%d\n", counter, isin(counter));
 	FntPrint(-1, "Image x %d y %d w %d h %d mode 0x%x\n", playerSkin.front.prect.x, playerSkin.front.prect.y, playerSkin.front.prect.w, playerSkin.front.prect.h, playerSkin.front.mode);
 	FntPrint(-1, "Model: %d tris, %d verts\n", playerModel.header->triangleCount, playerModel.header->vertexCount);
+	FntPrint(-1, "Trsf: (%d, %d, %d)\n", outPos.vx, outPos.vy, outPos.vz);
 	
 	// Draw the last created text stream
 	FntFlush(-1);
 
-	drawModel(&playerModel, &playerSkin, -40, counter >> 2);
-	drawModel(&shamblerModel, &shamblerSkin, 80, counter >> 2);
+	gte_SetBackColor(48, 48, 48);	// Ambient light color
+	gte_SetColorMatrix(&color_mtx);	// Light color and direction
 
-	// int r, g, b;
-	
-	// lerpcol(255, 255, 0, 255, 0, 0, (icos(counter * 32) + 4096) >> 1, &r, &g, &b);
-	// addTile(32, 32, 64, 64, r, g, b);
+	MATRIX mtx, lmtx;
+	RotMatrix(&rot, &mtx);
+	TransMatrix(&mtx, &pos);
 
-	// lerpcol(0, 255, 255, 0, 255, 0, (icos(counter * 24 + 512) + 4096) >> 1, &r, &g, &b);
-	// addTile(128, 160, 48, 48, r, g, b);
+	MulMatrix0(&light_mtx, &mtx, &lmtx);
 
-	// addColoredTriangle(260, 140, 220, 220, 300, 220, 0xFF0000, 0x00FF00, 0x0000FF, 0);
-	// addTexturedTriangle(260, 40, 220, 120, 300, 120, 0, 94, 74, 124, 58, 1, &playerSkin.front);
-	// addTexturedSprite(20, 140, 80, 80, &playerSkin.front);
-	// addTexturedSprite(80, 40, 154, 114, &shamblerSkin.front);
+	gte_SetRotMatrix(&mtx);
+	gte_SetTransMatrix(&mtx);
+	gte_SetLightMatrix(&lmtx);
+
+	drawModel(&playerModel, &playerSkin, -40, counter >> 2);
+	//drawModel(&shamblerModel, &shamblerSkin, 80, counter >> 2);
 }
 
 // Main function, program entrypoint