i did a lot

1 files changed, 234 insertions, 0 deletions

diff --git a/src/world.c b/src/world.c
new file mode 100644
index 0000000..a53055d
--- /dev/null
+++ b/src/world.c
@@ -0,0 +1,234 @@
+#include <cglm/cglm.h>
+#include <threads.h>
+
+#include "utils.h"
+#include "voxel.h"
+
+static RcChunk **world_get_chunk_entry(World *world, int cx, int cy, int cz)
+{
+	int side = RENDER_DISTANCE * 2 + 1;
+
+	ivec3 min, max;
+	glm_ivec3_subs(world->center, RENDER_DISTANCE, min);
+	glm_ivec3_adds(world->center, RENDER_DISTANCE, max);
+
+	if (cx < min[0] || cy < min[1] || cz < min[2])
+		return NULL;
+
+	if (cx > max[0] || cy > max[1] || cz > max[2])
+		return NULL;
+
+	int index = 0;
+	index += ((cx % side + side) % side);
+	index += ((cy % side + side) % side) * side;
+	index += ((cz % side + side) % side) * side * side;
+
+	return &world->chunks[index];
+}
+
+static void world_mark_chunk_for_update(World *world, int cx, int cy, int cz)
+{
+	RcChunk **entry, *inner;
+
+	entry = world_get_chunk_entry(world, cx, cy, cz);
+	if (entry == NULL)
+		return;
+
+	inner = *entry;
+	if (inner == NULL)
+		return;
+
+	if (inner->chunk.state >= CHUNK_MESHED)
+		inner->chunk.state = CHUNK_GENERATED;
+}
+
+static void world_reload_chunk(World *world, int cx, int cy, int cz)
+{
+	ivec3 pos = { cx, cy, cz };
+	RcChunk **entry, *inner;
+
+	entry = world_get_chunk_entry(world, cx, cy, cz);
+	if (entry == NULL)
+		return;
+
+	inner = *entry;
+	if (inner != NULL) {
+		if (glm_ivec3_eqv(inner->chunk.pos, pos)) {
+			return;
+		} else {
+			*entry = NULL;
+			world_lock(world);
+			rcchunk_drop(inner);
+			world_unlock(world);
+		}
+	}
+
+	inner = xalloc(sizeof(RcChunk));
+	inner->rc = 1;
+	chunk_init(&inner->chunk, cx, cy, cz);
+	chunk_generate(&inner->chunk, world->seed);
+	*entry = inner;
+
+	// mark neighboring chunks as mesh update needed
+	world_mark_chunk_for_update(world, cx - 1, cy, cz);
+	world_mark_chunk_for_update(world, cx + 1, cy, cz);
+	world_mark_chunk_for_update(world, cx, cy - 1, cz);
+	world_mark_chunk_for_update(world, cx, cy + 1, cz);
+	world_mark_chunk_for_update(world, cx, cy, cz - 1);
+	world_mark_chunk_for_update(world, cx, cy, cz + 1);
+}
+
+static void world_reload_chunks(World *world)
+{
+	ivec3 min, max;
+	glm_ivec3_subs(world->center, RENDER_DISTANCE, min);
+	glm_ivec3_adds(world->center, RENDER_DISTANCE, max);
+
+	// clang-format off
+	for (int cx = min[0]; cx <= max[0]; cx++)
+	for (int cy = min[1]; cy <= max[1]; cy++)
+	for (int cz = min[2]; cz <= max[2]; cz++) {
+		world_reload_chunk(world, cx, cy, cz);
+	}
+	// clang-format on
+}
+
+void world_init(World *world, int seed)
+{
+	int side = RENDER_DISTANCE * 2 + 1;
+	int size = side * side * side;
+	world->seed = seed;
+	world->loaded = false;
+	world->chunks = xzalloc(size * sizeof(RcChunk *));
+	glm_ivec3_zero(world->center);
+	mtx_init(&world->lock, mtx_plain);
+}
+
+void world_free(World *world)
+{
+	int side = RENDER_DISTANCE * 2 + 1;
+	int size = side * side * side;
+	world_lock(world);
+	for (int i = 0; i < size; i++) {
+		RcChunk **entry = &world->chunks[i];
+		if (entry == NULL)
+			continue;
+		rcchunk_drop(*entry);
+	}
+	free(world->chunks);
+	mtx_destroy(&world->lock);
+}
+
+void world_lock(World *world)
+{
+	mtx_lock(&world->lock);
+}
+
+void world_unlock(World *world)
+{
+	mtx_unlock(&world->lock);
+}
+
+void world_update(World *world, Camera *camera)
+{
+	ivec3 cp = CHUNK_VEC_V(camera->position);
+	if (!world->loaded || !glm_ivec3_eqv(world->center, cp)) {
+		// camera has moved, load new chunks
+		glm_ivec3_copy(cp, world->center);
+		world_reload_chunks(world);
+	}
+}
+
+void world_render(World *world, Renderer *renderer)
+{
+	RcChunk *rc_chunk;
+	ivec3 min, max;
+	int world_size, mesh_quota;
+
+	glm_ivec3_subs(world->center, RENDER_DISTANCE, min);
+	glm_ivec3_adds(world->center, RENDER_DISTANCE, max);
+
+	// how many chunk we want to mesh at most
+	world_size = RENDER_DISTANCE * 2 + 1;
+	mesh_quota = world_size * world_size / 10;
+
+	// clang-format off
+	for (int cx = min[0]; cx <= max[0]; cx++)
+	for (int cy = min[1]; cy <= max[1]; cy++)
+	for (int cz = min[2]; cz <= max[2]; cz++) {
+		rc_chunk = world_get_chunk(world, cx, cy, cz);
+		if (rc_chunk == NULL)
+			continue;
+
+		if (rc_chunk->chunk.state < CHUNK_MESHING && mesh_quota > 0) {
+			chunk_mesh(&rc_chunk->chunk, world);
+			mesh_quota--;
+		}
+
+		if (rc_chunk->chunk.has_mesh)
+			renderer_draw(renderer, &rc_chunk->chunk);
+
+		rcchunk_drop(rc_chunk);
+	}
+	// clang-format on
+}
+
+RcChunk *world_get_chunk(World *world, int cx, int cy, int cz)
+{
+	RcChunk **entry, *inner;
+	world_lock(world);
+	entry = world_get_chunk_entry(world, cx, cy, cz);
+	if (entry == NULL)
+		goto not_found;
+	inner = *entry;
+	if (inner == NULL)
+		goto not_found;
+	inner->rc += 1;
+	world_unlock(world);
+	return inner;
+
+not_found:
+	world_unlock(world);
+	return NULL;
+}
+
+bool world_is_generated(World *world, int cx, int cy, int cz)
+{
+	RcChunk *rc_chunk;
+	bool generated;
+
+	rc_chunk = world_get_chunk(world, cx, cy, cz);
+	if (rc_chunk == NULL)
+		return false;
+
+	generated = rc_chunk->chunk.state >= CHUNK_GENERATED;
+	rcchunk_drop(rc_chunk);
+
+	return generated;
+}
+
+Block world_get_block(World *world, int gx, int gy, int gz)
+{
+	RcChunk *rc_chunk;
+	Block block;
+	ivec3 lp = LOCAL_VEC(gx, gy, gz);
+	ivec3 cp = CHUNK_VEC(gx, gy, gz);
+
+	rc_chunk = world_get_chunk(world, cp[0], cp[1], cp[2]);
+	if (rc_chunk == NULL)
+		return AIR;
+
+	block = chunk_at(&rc_chunk->chunk, lp[0], lp[1], lp[2]);
+	rcchunk_drop(rc_chunk);
+
+	return block;
+}
+
+void rcchunk_drop(RcChunk *rc_chunk)
+{
+	rc_chunk->rc -= 1;
+	if (rc_chunk->rc == 0) {
+		chunk_free(&rc_chunk->chunk);
+		free(rc_chunk);
+	}
+}