From c52a5978823a77da3570cb73b985b928bb8358d9 Mon Sep 17 00:00:00 2001
From: John Tsiombikas <nuclear@member.fsf.org>
Date: Wed, 26 Oct 2022 03:25:32 +0300
Subject: [PATCH] optimization: fixed spawn points on color texture

---
 src/data.h     |    1 +
 src/gamescr.c  |   51 ++++++++++++++++++++++++++++++++++++++-------------
 src/voxscape.c |   25 +++++++++++++++----------
 3 files changed, 54 insertions(+), 23 deletions(-)

diff --git a/src/data.h b/src/data.h
index 4cfe6e4..dd8cc98 100644
--- a/src/data.h
+++ b/src/data.h
@@ -8,6 +8,7 @@
 	(((r) >> 3) | (((uint16_t)(g) & 0xf8) << 2) | (((uint16_t)(b) & 0xf8) << 7))
 
 #define VOX_SZ	512
+#define CMAP_SPAWN0	240
 
 #define SPRID(x, y)		(SPRID_BASE + ((y) * 4) + (x) / 4)
 
diff --git a/src/gamescr.c b/src/gamescr.c
index a84aa12..df11abc 100644
--- a/src/gamescr.c
+++ b/src/gamescr.c
@@ -36,8 +36,9 @@ struct enemy {
 	struct vox_object vobj;
 	short hp;
 	short anm;
-	short last_fire;
+	int last_fire;
 };
+#define ENEMY_VALID(e)	((e)->anm != 0)
 
 static uint16_t *framebuf;
 
@@ -55,7 +56,7 @@ static uint16_t oam[4 * MAX_SPR];
 static int dynspr_base, dynspr_count;
 
 
-#define MAX_ENEMIES	64
+#define MAX_ENEMIES	(256 - CMAP_SPAWN0)
 struct enemy enemies[MAX_ENEMIES];
 int num_enemies, total_enemies;
 static int energy;
@@ -80,15 +81,15 @@ struct screen *init_game_screen(void)
 
 static int gamescr_start(void)
 {
-	int i, sidx;
+	int i, j, sidx;
+	uint8_t *cptr;
+	struct enemy *enemy;
 
 	gba_setmode(4, DISPCNT_BG2 | DISPCNT_OBJ | DISPCNT_FB1);
 
 	vblperf_setcolor(0);
 
-	pos[0] = VOX_SZ << 15;
-	pos[1] = (VOX_SZ << 15) + 0x100000;
-	angle = 0x8000;
+	pos[0] = pos[1] = VOX_SZ << 15;
 
 	if(!(vox = vox_create(VOX_SZ, VOX_SZ, height_pixels, color_pixels))) {
 		panic(get_pc(), "vox_create");
@@ -131,19 +132,43 @@ static int gamescr_start(void)
 	wait_vblank();
 	dma_copy32(3, (void*)OAM_ADDR, oam, sidx * 2, 0);
 
-	num_enemies = 0;
-	total_enemies = 8;
+	num_enemies = total_enemies = 0;
 	energy = 5;
 
 	srand(0);
+	cptr = color_pixels;
+	for(i=0; i<VOX_SZ; i++) {
+		for(j=0; j<VOX_SZ; j++) {
+			if(*cptr == 0) {
+				/* player spawn point */
+				pos[0] = j << 16;
+				pos[1] = i << 16;
+
+			} else if(*cptr >= CMAP_SPAWN0) {
+				/* enemy spawn point */
+				enemy = enemies + *cptr - CMAP_SPAWN0;
+				if(enemy->anm) {
+					panic(get_pc(), "double spawn at %d,%d", j, i);
+				}
+				enemy->vobj.x = j;
+				enemy->vobj.y = i;
+				enemy->vobj.px = -1;
+				enemy->anm = 0xff;
+				enemy->hp = 2;
+				enemy->last_fire = 0;
+				total_enemies++;
+			}
+			cptr++;
+		}
+	}
+	/* check continuity */
 	for(i=0; i<total_enemies; i++) {
-		enemies[i].vobj.x = rand() % VOX_SZ;
-		enemies[i].vobj.y = rand() % VOX_SZ;
-		enemies[i].vobj.px = -1;
+		if(enemy->anm <= 0) {
+			panic(get_pc(), "discontinuous enemy list");
+		}
 		enemies[i].anm = rand() & 7;
-		enemies[i].hp = 2;
-		enemies[i].last_fire = 0;
 	}
+
 	vox_objects(vox, (struct vox_object*)enemies, total_enemies, sizeof *enemies);
 
 	nframes = 0;
diff --git a/src/voxscape.c b/src/voxscape.c
index 391c9ec..8ebc692 100644
--- a/src/voxscape.c
+++ b/src/voxscape.c
@@ -6,6 +6,7 @@
 #include <assert.h>
 #include "voxscape.h"
 #include "debug.h"
+#include "data.h"
 
 /* hardcoded dimensions for the GBA */
 #define FBWIDTH		240
@@ -19,6 +20,8 @@
 #define YMASK		0x1ff
 #define HSCALE		40
 
+/* XXX */
+#define OBJ_STRIDE_SHIFT	5
 
 #define NO_LERP
 
@@ -286,7 +289,7 @@ void vox_render_slice(struct voxscape *vox, int n)
 	int32_t x, y, len, xstep, ystep;
 	uint8_t color, last_col;
 	uint16_t *fbptr;
-	int proj;
+	/*int proj;*/
 	struct vox_object *obj;
 
 	z = vox->znear + n;
@@ -327,14 +330,12 @@ void vox_render_slice(struct voxscape *vox, int n)
 			vox->coltop[col] = hval;
 
 			/* check to see if there's an object here */
-			obj = vox->obj;
-			for(j=0; j<vox->num_obj; j++) {
-				if(obj->offs == offs) {
-					obj->px = col;
-					obj->py = colstart;
-					obj->scale = projlut[n];
-				}
-				obj = (struct vox_object*)((char*)obj + vox->obj_stride);
+			if(color >= CMAP_SPAWN0) {
+				int idx = color - CMAP_SPAWN0;
+				obj = (struct vox_object*)((char*)vox->obj + (idx << OBJ_STRIDE_SHIFT));
+				obj->px = col;
+				obj->py = colstart;
+				obj->scale = projlut[n];
 			}
 		}
 		x += xstep;
@@ -391,6 +392,11 @@ void vox_objects(struct voxscape *vox, struct vox_object *ptr, int count, int st
 	int i;
 	struct vox_object *obj;
 
+	if(stride != 1 << OBJ_STRIDE_SHIFT) {
+		panic(get_pc(), "optimization requires %d byte vox obj (got %d)",
+				1 << OBJ_STRIDE_SHIFT, stride);
+	}
+
 	vox->obj = ptr;
 	vox->num_obj = count;
 	vox->obj_stride = stride;
@@ -398,7 +404,6 @@ void vox_objects(struct voxscape *vox, struct vox_object *ptr, int count, int st
 	obj = ptr;
 	for(i=0; i<count; i++) {
 		obj->offs = obj->y * XSZ + obj->x;
-		emuprint("%d,%d -> %d", obj->x, obj->y, obj->offs);
 		obj = (struct vox_object*)((char*)obj + stride);
 	}
 }
-- 
1.7.10.4