WIP lightmap baking

6 files changed, 239 insertions, 6 deletions

diff --git a/3de.c b/3de.c
index 1c10e03..dc46522 100644
--- a/3de.c
+++ b/3de.c
@@ -80,6 +80,7 @@ void init_map(Map* m) {
 	for (i = 0; i < 0x100; i++) {
 		t[i] = map_data[i];
 	}
+	bake_map(m);
 }
 
 void draw_map(Renderer* r, const Player* p, const Map* m) {
diff --git a/config.h b/config.h
index 87a4824..8a95ce8 100644
--- a/config.h
+++ b/config.h
@@ -5,7 +5,8 @@
 #define app_memory_size (1024 * 1024 * 32)
 #define asset_preload_memory_size (1024 * 1024 * 8)
 #define gui_memory_size (1024 * 8)
-#define map_memory_size (1024 * 8)
+/* 8 megs for the map is not good. todo compress */
+#define map_memory_size (1024 * 1024 * 8)
 
 #define max_vp_w 2000
 #define max_vp_h 2000
@@ -15,5 +16,6 @@
 
 #define max_map_w 32
 #define max_map_h 32
+#define map_light_tile_size 16
 
 #endif
diff --git a/editor.c b/editor.c
index 645f7f7..86f7527 100644
--- a/editor.c
+++ b/editor.c
@@ -66,6 +66,9 @@ void edit_map(Editor* e, GUI* g, Map* m) {
 	mcs[1] = m->h * tile_display_size;
 	gui_btn(g, gui_cut_left(&t, gui_text_width("Load", 4) + 4), "Save");
 	gui_btn(g, gui_cut_left(&t, gui_text_width("Save", 4) + 4), "Load");
+	if (gui_btn(g, gui_cut_left(&t, gui_text_width("Bake Lights", 11) + 4), "Bake Lights")) {
+		bake_map(m);
+	}
 	g->uptr = m;
 	gui_scrollable(g, b, mcs, &map_ss, draw_map_scrollable);
 }
diff --git a/map.c b/map.c
index 5dbe236..d1dcbb8 100644
--- a/map.c
+++ b/map.c
@@ -1,7 +1,12 @@
 #include "map.h"
+#include "maths.h"
+#include <stdlib.h>
 
 int map_size(int w, int h) {
-	return sizeof(Map) + w * h * sizeof(Map_Tile);
+	return
+		sizeof(Map) +
+		w * h * sizeof(Map_Tile) +
+		w * h * sizeof(Map_Light_Tile);
 }
 
 Map_Tile* map_tiles(Map* m) {
@@ -11,3 +16,170 @@ Map_Tile* map_tiles(Map* m) {
 const Map_Tile* map_tilesc(const Map* m) {
 	return (Map_Tile*)&m[1];
 }
+
+Map_Light_Tile* map_light_tiles(Map* m) {
+	return (Map_Light_Tile*)&map_tiles(m)[m->w * m->h];
+}
+
+const Map_Light_Tile* map_light_tilesc(const Map* m) {
+	return (Map_Light_Tile*)&map_tilesc(m)[m->w * m->h];
+}
+
+typedef struct {
+	Line a, b;
+} Ray;
+
+void init_ray(Ray* r, const int* f, const int* t) {
+	int fa[2], ta[2];
+	int fb[2], tb[2];
+	fa[0] = f[0];
+	fa[1] = f[1];
+	ta[0] = t[0];
+	ta[1] = t[1];
+	fb[0] = f[0];
+	fb[1] = f[2];
+	tb[0] = t[0];
+	tb[1] = t[2];
+	init_line(&r->a, fa, ta);
+	init_line(&r->b, fb, tb);
+}
+
+void step_ray(Ray* r) {
+	step_line(&r->a);
+	while (r->a.x != r->b.x)
+		step_line(&r->b);
+}
+
+void get_ray(const Ray* r, int* d) {
+	d[0] = r->a.x;
+	d[1] = r->a.y;
+	d[2] = r->b.y;
+}
+
+int trace_ray(
+	Map* m,
+	const int* f,
+	const int* t
+) {
+	Ray r;
+	int pos[3], w[3];
+	init_ray(&r, f, t);
+	while (1) {
+		int mp[2], coord;
+		get_ray(&r, pos);
+		mp[0] = pos[0] >> fbits;
+		mp[1] = pos[1] >> fbits;
+		if (mp[0] < 0) goto end;
+		if (mp[1] < 0) goto end;
+		if (mp[0] >= m->w) goto end;
+		if (mp[1] >= m->h) goto end;
+		if (pos[2] < 0) { /* hit the floor */
+			goto end;
+		}
+		if (pos[2] >= f1) { /* hit the ceiling */
+			goto end;
+		}
+		coord = mp[0] + mp[1] * m->w;
+		if (map_tilesc(m)[coord]) {
+			goto end;
+		}
+		step_ray(&r);
+	}
+end:
+	return vec_dist(w, pos, t, 3) < 100;
+}
+
+void init_tile(Map* m, int tx, int ty, Map_Light_Tile* t) {
+	int i, x, y;
+	Map_Fragment full = {
+		{ 0xff, 0xff, 0xff, 0xff },
+		{ 0xff, 0xff, 0xff, 0xff }, {
+		{ 0xff, 0xff, 0xff, 0xff },
+		{ 0xff, 0xff, 0xff, 0xff },
+		{ 0xff, 0xff, 0xff, 0xff },
+		{ 0xff, 0xff, 0xff, 0xff },
+	}};
+	(void)m;
+	(void)tx;
+	(void)ty;
+	for (i = y = 0; y < map_light_tile_size; y++) {
+		for (x = 0; x < map_light_tile_size; x++, i++) {
+			t->fragments[i] = full;
+		}
+	}
+}
+
+void bake_tile(
+	Map* m,
+	int tx,
+	int ty,
+	Map_Light_Tile* t,
+	const Map_Light* light
+) {
+	int i, x, y, fr[3], w[3];
+	Map_Tile wall = map_tilesc(m)[tx + ty * m->w];
+	tx <<= fbits;
+	ty <<= fbits;
+	fr[0] = light->x;
+	fr[1] = light->y;
+	fr[2] = f1/2;
+	for (i = y = 0; y < map_light_tile_size; y++) {
+		for (x = 0; x < map_light_tile_size; x++, i++) {
+			int to[3];
+			int atten;
+			Colour c;
+			to[0] = tx + x * 32;
+			to[1] = ty + y * 32;
+			to[2] = f1;
+			atten = vec_dist(w, fr, to, 3);
+			atten /= 5;
+			atten = mini(
+				(f1 << fbits) / maxi(1, (atten * atten) >> fbits),
+				f1
+			) - 1;
+			c = col_scl(
+				light->c,
+				(unsigned char)(atten / 2)
+			);
+			if (trace_ray(m, fr, to))
+				t->fragments[i].u = c;
+			to[2] = 0;
+			if (trace_ray(m, fr, to))
+				t->fragments[i].d = c;
+		}
+	}
+}
+
+void bake_light(Map* m, const Map_Light* light) {
+	int x, y, i;
+	Map_Light_Tile* lt = map_light_tiles(m);
+	for (i = y = 0; y < m->h; y++) {
+		for (x = 0; x < m->w; x++, i++) {
+			bake_tile(m, x, y, &lt[i], light);
+		}
+	}
+}
+
+void bake_map(Map* m) {
+	Map_Light l = { f1 * 3, f1 * 3, f1, { 0xff, 0xff, 0xff, 0xff } };
+	bake_light(m, &l);
+}
+
+const Map_Fragment* sample_map_light(
+	const Map* m, 
+	int tx,
+	int ty,
+	int u,
+	int v
+) {
+	int coord;
+	const Map_Light_Tile* t =
+		&map_light_tilesc(m)[tx + ty * m->w];
+	int x = (u * map_light_tile_size) >> fbits;
+	int y = (v * map_light_tile_size) >> fbits;
+	x &= map_light_tile_size - 1;
+	y &= map_light_tile_size - 1;
+	coord = x + y * map_light_tile_size;
+	return &t->fragments[coord];
+}
+
diff --git a/map.h b/map.h
index 9e2a413..566b367 100644
--- a/map.h
+++ b/map.h
@@ -1,14 +1,42 @@
 #ifndef map_h
 #define map_h
 
+#include "config.h"
+#include "render.h"
+
 typedef struct Map {
 	int w, h;
 } Map;
 
+typedef struct {
+	Colour u, d;
+	Colour side[4]; /* left, right, north, south */
+} Map_Fragment;
+
+typedef struct {
+	int x, y;
+	int brightness;
+	Colour c;
+} Map_Light;
+
+typedef struct {
+	Map_Fragment fragments[map_light_tile_size * map_light_tile_size];
+} Map_Light_Tile;
+
 typedef unsigned Map_Tile;
 
 int map_size(int w, int h);
 Map_Tile* map_tiles(Map* m);
 const Map_Tile* map_tilesc(const Map* m);
+Map_Light_Tile* map_light_tiles(Map* m);
+const Map_Light_Tile* map_light_tilesc(const Map* m);
+void bake_map(Map* m);
+const Map_Fragment* sample_map_light(
+	const Map* m, 
+	int tx,
+	int ty,
+	int u,
+	int v
+);
 
 #endif
diff --git a/render.c b/render.c
index 3e5758b..f50dd04 100644
--- a/render.c
+++ b/render.c
@@ -785,12 +785,29 @@ void ren_map(
 			int t = ((2 * x) << (fbits * 2)) / w - f1;
 			int coordc = x + y * r->vp[0];
 			int coordf = x + ((hhi - y) + hhi) * r->vp[0];
-			int ifloor[2];
+			int ifloor[2], mc[2];
+			const Map_Fragment* light;
+			Colour c;
 			t = (t + f1) / 2;
 			ifloor[0] = floor[0] + ((t * (floor[2] - floor[0])) >> fbits);
 			ifloor[1] = floor[1] + ((t * (floor[3] - floor[1])) >> fbits);
-			r->t[coordc] = sample_tex(ceiling, ifloor[0], ifloor[1]);
-			r->t[coordf] = sample_tex(floort,  ifloor[0], ifloor[1]);
+			mc[0] = ifloor[0] >> fbits;
+			mc[1] = ifloor[1] >> fbits;
+			if (mc[0] < 0) continue;
+			if (mc[1] < 0) continue;
+			if (mc[0] >= map->w) continue;
+			if (mc[1] >= map->h) continue;
+			light = sample_map_light(
+				map,
+				mc[0],
+				mc[1],
+				ifloor[0],
+				ifloor[1]
+			);
+			c = sample_tex(ceiling, ifloor[0], ifloor[1]);
+			r->t[coordc] = col_mul(c, light->u);
+			c = sample_tex(floort, ifloor[0], ifloor[1]);
+			r->t[coordf] = col_mul(c, light->d);
 		}
 	}
 	for (x = r->clip[0]; x < r->clip[2]; x++) {
@@ -819,17 +836,19 @@ void ren_map(
 			dside[1] = (((mp[1] << fbits) + f1 - pos[1]) * delta[1]) >> fbits;
 		}
 		while (1) {
-			int dist, u;
+			int dist, u, side;
 			if (dside[0] < dside[1]) {
 				dside[0] += delta[0];
 				mp[0] += step[0];
 				dist = dside[0] - delta[0];
 				u = pos[1] + ((dist * d[1]) >> fbits);
+				side = d[0] < 0;
 			} else {
 				dside[1] += delta[1];
 				mp[1] += step[1];
 				dist = dside[1] - delta[1];
 				u = pos[0] + ((dist * d[0]) >> fbits);
+				side = 2 + (d[1] < 0);
 			}
 			if (mp[0] < 0) break;
 			if (mp[1] < 0) break;
@@ -845,6 +864,14 @@ void ren_map(
 					int coord = x + y * r->vp[0];
 					int v = ((y - sy) << fbits) / (ey - sy);
 					Colour c = sample_tex(texture, u, v);
+					const Map_Fragment* light = sample_map_light(
+						map,
+						mp[0],
+						mp[1],
+						u,
+						v
+					);
+					c = col_mul(c, light->side[side]);
 					r->d[coord] = dist;
 					r->t[coord] = c;
 				}