fix chunkloading and unloading on client

2 files changed, 159 insertions, 137 deletions

diff --git a/client/main.ha b/client/main.ha
index 9b8f92b..0f4b1b8 100644
--- a/client/main.ha
+++ b/client/main.ha
@@ -7,12 +7,12 @@ use net::dial;
 use unix::poll;
 
 use drawing;
-use drawing::{pos,CHUNKSIZE};
+use drawing::{pos,CHUNKSIZE,picture};
 use client::paintui;
 use packet_reader;
 use packet_reader::{VERSION};
 
-def NCHUNKS = 16;
+def NSURFS = 16;
 
 def WIN_H: i32 = 480;
 def WIN_W: i32 = 640;
@@ -27,22 +27,7 @@ export fn main() void = {
 
 	const wsurf = sdl2::SDL_GetWindowSurface(win)!;
 
-	let offs: []pos = [];
-	for (let x = -1; x < 3; x+=1) for (let y = -1; y < 3; y+=1)
-		append(offs, (1024*1024+x*CHUNKSIZE,y*CHUNKSIZE));
-
-	let pictures: []drawing::picture = alloc([],NCHUNKS);
-	let picture_surfaces: []*sdl2::SDL_Surface = alloc([], NCHUNKS);
-	for (let i = 0z; i < NCHUNKS; i +=1){
-		const surf = sdl2::SDL_CreateRGBSurface(0,
-			CHUNKSIZE, CHUNKSIZE, 32, 0xff0000, 0xff00, 0xff, 0)!;
-		append(picture_surfaces, surf);
-		append(pictures, picture_from_surface(surf, offs[i]));
-	};
-	for (const p &.. pictures) {
-		drawing::clear_picture(p, 0x00ff00);
-		drawing::outline_picture(p);
-	};
+	let pmgr = picture_mgr { ... };
 
 	// connect to server
 	const conn = match(dial::dial("tcp","localhost","41460")) {
@@ -51,6 +36,7 @@ export fn main() void = {
 			fmt::fatal("couldn't connect to server:",net::strerror(err));
 	};
 
+	// version check
 	let byte = [0u8];
 	match (io::read(conn, byte)) {
 	case let e: io::error =>
@@ -60,7 +46,6 @@ export fn main() void = {
 			byte[0], VERSION);
 	};
 				
-	
 	const pollfd: [1]poll::pollfd = [ poll::pollfd {
 		fd = conn, events=poll::event::POLLIN, revents = 0
 	}];
@@ -74,16 +59,14 @@ export fn main() void = {
 	let n = 0;
 	let lasttime = sdl2::SDL_GetTicks();
 
-	let requested_chunks: []pos = [];
-
 	// in SCREEN coords
 	let mouse_pos: pos = (0,0);
 	let mouse_down = false;
-	request_visible_chunks(pictures, conn, camera_pos, &requested_chunks);
 
 
-	const win_pic = picture_from_surface(wsurf, (9,9));
+	process_chunk_loadedness(&pmgr, conn, camera_pos);
 
+	const win_pic = picture_from_surface(wsurf, (9,9));
 	for (!quit) {
 		const did_move = do_movement(&camera_pos);
 
@@ -124,13 +107,13 @@ export fn main() void = {
 		match (paintui::tick(&pstate, mouse_pos_world, mouse_down)) {
 		case void => yield;
 		case let op: drawing::op =>
-			drawing::perform(pictures, op);
+			perform_drawop(&pmgr, op);
 			packet_reader::send(conn, op: packet_reader::packet_drawop)!;
 		};
 
 		if (did_move) {
 			packet_reader::send(conn, camera_pos: packet_reader::packet_position)!;
-			request_visible_chunks(pictures, conn, camera_pos, &requested_chunks);
+			process_chunk_loadedness(&pmgr, conn, camera_pos);
 		};
 
 		const n = poll::poll(pollfd, poll::NONBLOCK)!;
@@ -139,36 +122,17 @@ export fn main() void = {
 			for (const packet => packet_reader::next(&packet_reader)!) {
 				match (packet) {
 				case let op: packet_reader::packet_drawop =>
-					drawing::perform(pictures, op);
+					perform_drawop(&pmgr, op);
 				case let packet: packet_reader::packet_sendchunk =>
-					assert(packet.world_pos.0 % CHUNKSIZE == 0
-							&& packet.world_pos.1 % CHUNKSIZE == 0, "bad chunk world pos");
-					const pic = find_picture_for_chunkdata(camera_pos, packet.world_pos, pictures);
-					pic.world_pos = packet.world_pos;
-					pic.d[..len(packet.chunk_data)] = packet.chunk_data[..];
-
-					for (let i = 0z; i < len(requested_chunks); i += 1) {
-						const rc = requested_chunks[i];
-						if (rc.0 == packet.world_pos.0 && rc.1 == packet.world_pos.1) {
-							delete(requested_chunks[i]);
-							fmt::printfln("fulfilling chunk request {},{}",
-								packet.world_pos.0, packet.world_pos.1)!;
-							break;
-						};
-					};
-
+					enact_chunkdata(&pmgr, packet, camera_pos);
 				};
 			};
 		};
 
-
 		drawing::clear_picture(&win_pic, 0xdddddd);
 
-		for (let i = 0z; i < len(pictures); i += 1) {
-			const psurf = picture_surfaces[i];
-			const pic = &pictures[i];
-			render_picture(pic, psurf, wsurf, camera_pos);
-		};
+		for (const pic &.. pmgr.pictures)
+			render_picture(pic, wsurf, camera_pos);
 
 		drawing::circle_hollow(&win_pic, mouse_pos, paintui::sizes[pstate.size_idx]: i32, pstate.color);
 
@@ -185,8 +149,8 @@ fn picture_from_surface(surf: *sdl2::SDL_Surface, world_pos: pos) drawing::pictu
 	world_pos = world_pos,
 };
 
-fn render_picture(pic: *drawing::picture, surf: *sdl2::SDL_Surface, winsurf: *sdl2::SDL_Surface, camera_pos: pos) void = {
-	sdl2::SDL_BlitSurface(surf, null, winsurf, &sdl2::SDL_Rect{
+fn render_picture(pic: *picture_c, winsurf: *sdl2::SDL_Surface, camera_pos: pos) void = {
+	sdl2::SDL_BlitSurface(pic.surface, null, winsurf, &sdl2::SDL_Rect{
 		x = pic.world_pos.0 - camera_pos.0, y = pic.world_pos.1 - camera_pos.1, ...
 	})!;
 };
@@ -216,91 +180,4 @@ fn do_movement(pos: *pos) bool = {
 	return did_move;
 };
 
-fn is_picture_visible(camera_pos: pos, pic_pos: pos) bool = {
-	const s_min: pos = camera_pos;
-	const s_max: pos = (camera_pos.0 + WIN_W, camera_pos.1 + WIN_H);
-	const p_min: pos = pic_pos;
-	const p_max: pos = (pic_pos.0 + CHUNKSIZE: i32, pic_pos.1 + CHUNKSIZE: i32);
-	return (s_min.0 <= p_max.0 && s_max.0 >= p_min.0)
-			&& (s_min.1 <= p_max.1 && s_max.1 >= p_min.1);
-};
-
-fn find_picture_for_chunkdata(camera_pos: pos, world_pos: pos, pictures: []drawing::picture) *drawing::picture = {
-	// if we have one with that exact worldpos, return that
-	// otherwise find one that isn't visible
-
-	let invisible: nullable *drawing::picture = null;
-	
-	for (const pic &.. pictures) {
-		if (pic.world_pos.0 == world_pos.0 && pic.world_pos.1 == world_pos.1) {
-			// fmt::printfln("found already pic at {},{}",pic.world_pos.0, pic.world_pos.1)!;
-			return pic;
-		};
-		if (invisible == null && !is_picture_visible(camera_pos, pic.world_pos)) {
-			// fmt::printfln("can recycle pic at {},{}",pic.world_pos.0,pic.world_pos.1)!;
-			invisible = pic;
-		};
-	};
-
-	match (invisible) {
-	case null => abort("couldn't find offscreen picture???");
-	case let p: *drawing::picture => return p;
-	};
-
-};
-
-
-
-fn floor_div(a: i32, b: i32) i32 = {
-	if (a < 0) return -1-floor_div(-(a+1),b);
-	return a / b;
-};
-fn find_chunk(pictures: []drawing::picture, world_pos: pos)
-		nullable *drawing::picture = {
-	for (const pic &.. pictures) {
-		if (pic.world_pos.0 == world_pos.0
-			&& pic.world_pos.1 == world_pos.1) {
-			return pic;
-		};
-	};
-	return null;
-};
-
-fn request_visible_chunks(
-	pictures: []drawing::picture,
-	conn: net::socket,
-	camera_pos: pos,
-	requested_chunks: *[]pos,
-) void = {
-	const x0 = CHUNKSIZE*floor_div(camera_pos.0,CHUNKSIZE);
-	const y0 = CHUNKSIZE*floor_div(camera_pos.1,CHUNKSIZE);
-
-	for (let dx = 0i32; dx < 3; dx += 1) for (let dy = 0i32; dy < 3; dy += 1) {
-		let world_pos = (x0+CHUNKSIZE*dx, y0+CHUNKSIZE*dy): pos;
-
-		for (const rc .. requested_chunks) {
-			if (rc.0 == world_pos.0 && rc.1 == world_pos.1) {
-				fmt::printfln("not requesting {},{} again", rc.0, rc.1)!;
-				return;
-			};
-		};
-
-
-		if (!is_picture_visible(camera_pos, world_pos)) {
-			// fmt::printfln("invisible {},{}", world_pos.0, world_pos.1)!;
-			continue;
-		};
-		// fmt::printfln("visible {},{}, checking availability", world_pos.0, world_pos.1)!;
-		match (find_chunk(pictures,world_pos)) {
-		case *drawing::picture =>
-			// fmt::printfln("\talready got that one")!;
-			yield;
-		case null =>
-			fmt::printfln("\trequesting {},{}", world_pos.0, world_pos.1)!;
-			packet_reader::send(conn, world_pos: packet_reader::packet_reqchunk)!;
-			append(requested_chunks, world_pos);
-		};
-	};
-};
-
 
diff --git a/client/pictures.ha b/client/pictures.ha
new file mode 100644
index 0000000..1db3954
--- /dev/null
+++ b/client/pictures.ha
@@ -0,0 +1,145 @@
+use fmt;
+use net;
+
+use sdl2;
+
+use drawing::{picture,pos,CHUNKSIZE};
+use drawing;
+use packet_reader;
+
+type picture_mgr = struct {
+	pictures: []picture_c,
+	requests: []pos,
+};
+
+type picture_c = struct {
+	picture,
+	surface: *sdl2::SDL_Surface,
+};
+
+
+fn is_picture_visible(camera_pos: pos, pic_pos: pos) bool = {
+	const s_min: pos = camera_pos;
+	const s_max: pos = (camera_pos.0 + WIN_W, camera_pos.1 + WIN_H);
+	const p_min: pos = pic_pos;
+	const p_max: pos = (pic_pos.0 + CHUNKSIZE: i32, pic_pos.1 + CHUNKSIZE: i32);
+	return (s_min.0 <= p_max.0 && s_max.0 >= p_min.0)
+			&& (s_min.1 <= p_max.1 && s_max.1 >= p_min.1);
+};
+
+fn find_picture_by_pos(pmgr: *picture_mgr, world_pos: pos)
+		nullable *picture = {
+	for (const pic &.. pmgr.pictures) {
+		if (pic.world_pos.0 == world_pos.0
+			&& pic.world_pos.1 == world_pos.1) {
+			return pic;
+		};
+	};
+	return null;
+};
+
+// called when a new chunkdata packet comes in
+fn enact_chunkdata(pmgr: *picture_mgr,
+	packet: packet_reader::packet_sendchunk,
+	camera_pos: pos,
+) void = {
+	assert(packet.world_pos.0 % CHUNKSIZE == 0
+			&& packet.world_pos.1 % CHUNKSIZE == 0,
+		"bad chunk world pos");
+	assert(len(packet.chunk_data) == CHUNKSIZE*CHUNKSIZE,
+		"bad chunk data size");
+
+	const surf = sdl2::SDL_CreateRGBSurface(0,
+		CHUNKSIZE, CHUNKSIZE, 32, 0xff0000, 0xff00, 0xff, 0)!;
+	append(pmgr.pictures, picture_c {
+		w = CHUNKSIZE,
+		h = CHUNKSIZE,
+		d = (surf.pixels as *opaque: *[*]u32),
+		world_pos = packet.world_pos,
+		surface = surf,
+	});
+
+	const p = &pmgr.pictures[len(pmgr.pictures)-1];
+	p.d[..p.w*p.h] = packet.chunk_data[..];
+
+	// delete extant request
+	for (let i = 0z; i < len(pmgr.requests); i += 1) {
+		const rc = pmgr.requests[i];
+		if (rc.0 == packet.world_pos.0 && rc.1 == packet.world_pos.1) {
+			delete(pmgr.requests[i]);
+			break;
+		};
+	};
+};
+
+fn floor_div(a: i32, b: i32) i32 = {
+	if (a < 0) return -1-floor_div(-(a+1),b);
+	return a / b;
+};
+
+
+fn is_request_inflight(pmgr: *picture_mgr, world_pos: pos) bool = {
+	for (const rc .. pmgr.requests)
+		if (rc.0 == world_pos.0 && rc.1 == world_pos.1)
+			return true;
+	return false;
+};
+
+// called on startup and on camera movement
+// 	for each loaded chunk not visible, unload it
+// 	for each chunk that should be visible that isn't loaded
+// 		and which hasn't already been requested,
+// 	request it.
+fn process_chunk_loadedness(
+	pmgr: *picture_mgr,
+	conn: net::socket,
+	camera_pos: pos,
+) void = {
+
+	// unload all invisible chunks
+	for (let i1 = len(pmgr.pictures); i1 > 0; i1 -= 1) {
+		const i = i1 - 1;
+		const pic = pmgr.pictures[i];
+		if (!is_picture_visible(camera_pos, pic.world_pos)) {
+			fmt::printfln("## unloading {},{}", pic.world_pos.0, pic.world_pos.1)!;
+			delete(pmgr.pictures[i]);
+		};
+	};
+
+
+	const x0 = CHUNKSIZE*floor_div(camera_pos.0,CHUNKSIZE);
+	const y0 = CHUNKSIZE*floor_div(camera_pos.1,CHUNKSIZE);
+
+	// use a 3x3 window for 'chunks that might need to be loaded'
+	for (let dx = 0i32; dx < 3; dx += 1) {
+		for (let dy = 0i32; dy < 3; dy += 1) {
+			const world_pos = (x0 + CHUNKSIZE*dx, y0 + CHUNKSIZE*dy): pos;
+			const visible = is_picture_visible(camera_pos, world_pos);
+			const loaded = !(find_picture_by_pos(pmgr, world_pos) is null);
+			const requested = is_request_inflight(pmgr, world_pos);
+
+			if (!visible) {
+				fmt::printfln("\tnot visible {},{}", world_pos.0, world_pos.1)!;
+				continue;
+			};
+			if (loaded) {
+				fmt::printfln("\talready loaded {},{}", world_pos.0, world_pos.1)!;
+				continue;
+			};
+			if (requested) {
+				fmt::printfln("\tnot requesting again {},{}", world_pos.0, world_pos.1)!;
+				continue;
+			};
+
+			fmt::printfln("!! requesting {},{}", world_pos.0, world_pos.1)!;
+			packet_reader::send(conn, world_pos: packet_reader::packet_reqchunk)!;
+			append(pmgr.requests, world_pos);
+		};
+	};
+};
+
+
+fn perform_drawop(pmgr: *picture_mgr, op: drawing::op) void = {
+	for (const pic &.. pmgr.pictures)
+		drawing::perform(pic, op);
+};