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raw | patch | inline | side by side (parent: ac11c0b)
raw | patch | inline | side by side (parent: ac11c0b)
author | Ketmar Dark <ketmar@ketmar.no-ip.org> | |
Tue, 5 Sep 2017 19:14:35 +0000 (22:14 +0300) | ||
committer | Ketmar Dark <ketmar@ketmar.no-ip.org> | |
Tue, 5 Sep 2017 19:56:20 +0000 (22:56 +0300) |
src/game/g_grid.pas | patch | blob | history |
diff --git a/src/game/g_grid.pas b/src/game/g_grid.pas
index 092f13ee201a53a54939da7ceced246ef4e39c24..e7e7f016fc0e940b81fa3a04610cc408721f3e57 100644 (file)
--- a/src/game/g_grid.pas
+++ b/src/game/g_grid.pas
interface
+const
+ GridTileSize = 32; // must be power of two!
type
TBodyProxyId = Integer;
public
type TGridQueryCB = function (obj: ITP; tag: Integer): Boolean is nested; // return `true` to stop
type TGridRayQueryCB = function (obj: ITP; tag: Integer; x, y, prevx, prevy: Integer): Boolean is nested; // return `true` to stop
-
type TCellQueryCB = procedure (x, y: Integer) is nested; // top-left cell corner coords
const TagDisabled = $40000000;
private
const
- GridDefaultTileSize = 32; // must be power of two!
GridCellBucketSize = 8; // WARNING! can't be less than 2!
public
private
//mTileSize: Integer;
- const mTileSize = GridDefaultTileSize;
+ const mTileSize = GridTileSize;
type TGetProxyFn = function (pxidx: Integer): PBodyProxyRec of object;
public
// no callback: return object of the nearest hit or nil
// if `inverted` is true, trace will register bodies *exluding* tagmask
//WARNING: don't change tags in callbacks here!
- function traceRay (const x0, y0, x1, y1: Integer; cb: TGridRayQueryCB; tagmask: Integer=-1): ITP; overload;
- function traceRay (out ex, ey: Integer; const ax0, ay0, ax1, ay1: Integer; cb: TGridRayQueryCB; tagmask: Integer=-1): ITP;
+ function traceRayOld (const x0, y0, x1, y1: Integer; cb: TGridRayQueryCB; tagmask: Integer=-1): ITP; overload;
+ function traceRayOld (out ex, ey: Integer; const ax0, ay0, ax1, ay1: Integer; cb: TGridRayQueryCB; tagmask: Integer=-1): ITP;
+
+ //WARNING: don't modify grid while any query is in progress (no checks are made!)
+ // you can set enabled/disabled flag, tho (but iterator can still return objects disabled inside it)
+ // cb with `(nil)` will be called before processing new tile
+ // no callback: return object of the nearest hit or nil
+ // if `inverted` is true, trace will register bodies *exluding* tagmask
+ // `cb` is used unconvetionally here: if it returns `false`, tracer will ignore the object
+ //WARNING: don't change tags in callbacks here!
+ function traceRay (const x0, y0, x1, y1: Integer; cb: TGridQueryCB; tagmask: Integer=-1): ITP; overload;
+ function traceRay (out ex, ey: Integer; const ax0, ay0, ax1, ay1: Integer; cb: TGridQueryCB; tagmask: Integer=-1): ITP;
// return `false` if we're still inside at the end
// line should be either strict horizontal, or strict vertical, otherwise an exception will be thrown
// `true`: endpoint will point at the last "inside" pixel
// `false`: endpoint will be (ax1, ay1)
+ //WARNING: don't change tags in callbacks here!
function traceOrthoRayWhileIn (out ex, ey: Integer; ax0, ay0, ax1, ay1: Integer; tagmask: Integer=-1): Boolean;
//WARNING: don't modify grid while any query is in progress (no checks are made!)
// trace box with the given velocity; return object hit (if any)
// `cb` is used unconvetionally here: if it returns `false`, tracer will ignore the object
+ //WARNING: don't change tags in callbacks here!
function traceBox (out ex, ey: Integer; const ax0, ay0, aw, ah: Integer; const dx, dy: Integer; cb: TGridQueryCB; tagmask: Integer=-1): ITP;
// debug
end;
+type
+ // common structure for all line tracers
+ TLineWalker = record
+ public
+ const TileSize = GridTileSize;
+
+ private
+ wx0, wy0, wx1, wy1: Integer; // window coordinates
+ stx, sty: Integer; // "steps" for x and y axes
+ dx2, dy2: Integer; // "double lengthes" for x and y axes
+ xd, yd: Integer; // current coord
+ e: Integer; // "error" (as in bresenham algo)
+ term: Integer; // end for xd (xd = term: done)
+ //xptr, yptr: PInteger;
+ xyswapped: Boolean; // true: xd is y
+
+ public
+ // call `setyp` after this
+ constructor Create (minx, miny, maxx, maxy: Integer);
+
+ procedure setClip (minx, miny, maxx, maxy: Integer); inline;
+
+ // this will use `w[xy][01]` to clip coords
+ // return `false` if the whole line was clipped away
+ // on `true`, you should process first point, and go on
+ function setup (x0, y0, x1, y1: Integer): Boolean;
+
+ // call this *after* doing a step
+ // WARNING! if you will do a step when this returns `true`, you will fall into limbo
+ function done (): Boolean; inline;
+
+ // as you will prolly call `done()` after doing a step anyway, this will do it for you
+ // move to next point, return `true` when the line is complete (i.e. you should stop)
+ function step (): Boolean; inline;
+
+ // move to next tile; return `true` if the line is complete (and walker state is undefined then)
+ function stepToNextTile (): Boolean; inline;
+
+ // hack for line-vs-aabb; NOT PROPERLY TESTED!
+ procedure getPrevXY (out ox, oy: Integer); inline;
+
+ // current coords
+ function x (): Integer; inline;
+ function y (): Integer; inline;
+
+ procedure getXY (out ox, oy: Integer); inline;
+
+ // move directions; always [-1..1] (can be zero!)
+ function dx (): Integer; inline;
+ function dy (): Integer; inline;
+ end;
+
+
// you are not supposed to understand this
// returns `true` if there is an intersection, and enter coords
// enter coords will be equal to (x0, y0) if starting point is inside the box
@@ -250,8 +315,8 @@ function sweepAABB (mex0, mey0, mew, meh: Integer; medx, medy: Integer; itx0, it
function distanceSq (x0, y0, x1, y1: Integer): Integer; inline;
procedure swapInt (var a: Integer; var b: Integer); inline;
-function minInt (a, b: Integer): Integer; inline;
-function maxInt (a, b: Integer): Integer; inline;
+//function minInt (a, b: Integer): Integer; inline;
+//function maxInt (a, b: Integer): Integer; inline;
implementation
// ////////////////////////////////////////////////////////////////////////// //
procedure swapInt (var a: Integer; var b: Integer); inline; var t: Integer; begin t := a; a := b; b := t; end;
-function minInt (a, b: Integer): Integer; inline; begin if (a < b) then result := a else result := b; end;
-function maxInt (a, b: Integer): Integer; inline; begin if (a > b) then result := a else result := b; end;
+//function minInt (a, b: Integer): Integer; inline; begin if (a < b) then result := a else result := b; end;
+//function maxInt (a, b: Integer): Integer; inline; begin if (a > b) then result := a else result := b; end;
function distanceSq (x0, y0, x1, y1: Integer): Integer; inline; begin result := (x1-x0)*(x1-x0)+(y1-y0)*(y1-y0); end;
+// ////////////////////////////////////////////////////////////////////////// //
+constructor TLineWalker.Create (minx, miny, maxx, maxy: Integer);
+begin
+ setClip(minx, miny, maxx, maxy);
+end;
+
+procedure TLineWalker.setClip (minx, miny, maxx, maxy: Integer); inline;
+begin
+ // clip rectange
+ wx0 := minx;
+ wy0 := miny;
+ wx1 := maxx;
+ wy1 := maxy;
+end;
+
+function TLineWalker.done (): Boolean; inline; begin result := (xd = term); end;
+
+function TLineWalker.step (): Boolean; inline;
+begin
+ if (e >= 0) then begin yd += sty; e -= dx2; end else e += dy2;
+ xd += stx;
+ result := (xd = term);
+end;
+
+// move to next tile; return `true` if the line is complete (and walker state is undefined then)
+function TLineWalker.stepToNextTile (): Boolean; inline;
+var
+ ex, ey, wklen, f: Integer;
+begin
+ result := false;
+
+ //writeln('stx=', stx, '; sty=', sty);
+
+ // ortho?
+ if (sty = 0) then
+ begin
+ // only xd
+ assert(sty <> 0);
+ if (stx < 0) then
+ begin
+ // xd: to left edge
+ xd := (xd and (not (TileSize-1)))-1;
+ result := (xd <= term);
+ exit;
+ end
+ else
+ begin
+ // xd: to right edge
+ xd := (xd or (TileSize-1))+1;
+ result := (xd >= term);
+ exit;
+ end;
+ end;
+
+ assert(stx <> 0); // invariant
+
+ // not ortho
+ if (sty < 0) then ey := (yd and (not (TileSize-1)))-1 else ey := (yd or (TileSize-1))+1;
+
+ //FIXME: do some math to avoid single-stepping
+ if (stx < 0) then
+ begin
+ // xd: to left edge
+ ex := (xd and (not (TileSize-1)))-1;
+ if (ex <= term) then begin result := true; exit; end;
+ wklen := xd-ex;
+ end
+ else
+ begin
+ // xd: to right edge
+ ex := (xd or (TileSize-1))+1;
+ if (ex >= term) then begin result := true; exit; end;
+ wklen := ex-xd;
+ end;
+
+ //writeln('xd=', xd, '; yd=', yd, '; ex=', ex, '; ey=', ey, '; term=', term, '; wklen=', wklen);
+
+ for f := wklen downto 1 do
+ begin
+ // do step
+ if (e >= 0) then begin yd += sty; e -= dx2; end else e += dy2;
+ xd += stx;
+ if (xd = term) then begin result := true; exit; end;
+ if (xd = ex) or (yd = ey) then exit; // done
+ end;
+
+ raise Exception.Create('TLineWalker.stepToNextTile: the thing that should not be!');
+end;
+
+// NOT TESTED!
+procedure TLineWalker.getPrevXY (out ox, oy: Integer); inline;
+begin
+ //writeln('e=', e, '; dx2=', dx2, '; dy2=', dy2);
+ if xyswapped then
+ begin
+ if (e >= 0) then ox := yd-sty else ox := yd;
+ oy := xd-stx;
+ end
+ else
+ begin
+ if (e >= 0) then oy := yd-sty else oy := yd;
+ ox := xd-stx;
+ end;
+end;
+
+function TLineWalker.x (): Integer; inline; begin if xyswapped then result := yd else result := xd; end;
+function TLineWalker.y (): Integer; inline; begin if xyswapped then result := xd else result := yd; end;
+procedure TLineWalker.getXY (out ox, oy: Integer); inline; begin if xyswapped then begin ox := yd; oy := xd; end else begin ox := xd; oy := yd; end; end;
+
+function TLineWalker.dx (): Integer; inline; begin if xyswapped then result := stx else result := sty; end;
+function TLineWalker.dy (): Integer; inline; begin if xyswapped then result := sty else result := stx; end;
+
+function TLineWalker.setup (x0, y0, x1, y1: Integer): Boolean;
+ procedure swapInt (var a: Integer; var b: Integer); inline; var t: Integer; begin t := a; a := b; b := t; end;
+var
+ dsx, dsy: Integer; // "lengthes" for x and y axes
+ rem: Integer;
+ xfixed: Boolean;
+ temp: Integer;
+begin
+ result := false;
+ xyswapped := false;
+
+ // horizontal setup
+ if (x0 < x1) then
+ begin
+ // from left to right
+ if (x0 > wx1) or (x1 < wx0) then exit; // out of screen
+ stx := 1; // going right
+ end
+ else
+ begin
+ // from right to left
+ if (x1 > wx1) or (x0 < wx0) then exit; // out of screen
+ stx := -1; // going left
+ x0 := -x0;
+ x1 := -x1;
+ wx0 := -wx0;
+ wx1 := -wx1;
+ swapInt(wx0, wx1);
+ end;
+
+ // vertical setup
+ if (y0 < y1) then
+ begin
+ // from top to bottom
+ if (y0 > wy1) or (y1 < wy0) then exit; // out of screen
+ sty := 1; // going down
+ end
+ else
+ begin
+ // from bottom to top
+ if (y1 > wy1) or (y0 < wy0) then exit; // out of screen
+ sty := -1; // going up
+ y0 := -y0;
+ y1 := -y1;
+ wy0 := -wy0;
+ wy1 := -wy1;
+ swapInt(wy0, wy1);
+ end;
+
+ dsx := x1-x0;
+ dsy := y1-y0;
+
+ if (dsx < dsy) then
+ begin
+ xyswapped := true;
+ //xptr := @yd;
+ //yptr := @xd;
+ swapInt(x0, y0);
+ swapInt(x1, y1);
+ swapInt(dsx, dsy);
+ swapInt(wx0, wy0);
+ swapInt(wx1, wy1);
+ swapInt(stx, sty);
+ end
+ else
+ begin
+ //xptr := @xd;
+ //yptr := @yd;
+ end;
+
+ dx2 := 2*dsx;
+ dy2 := 2*dsy;
+ xd := x0;
+ yd := y0;
+ e := 2*dsy-dsx;
+ term := x1;
+
+ xfixed := false;
+ if (y0 < wy0) then
+ begin
+ // clip at top
+ temp := dx2*(wy0-y0)-dsx;
+ xd += temp div dy2;
+ rem := temp mod dy2;
+ if (xd > wx1) then exit; // x is moved out of clipping rect, nothing to do
+ if (xd+1 >= wx0) then
+ begin
+ yd := wy0;
+ e -= rem+dsx;
+ if (rem > 0) then begin Inc(xd); e += dy2; end;
+ xfixed := true;
+ end;
+ end;
+
+ if (not xfixed) and (x0 < wx0) then
+ begin
+ // clip at left
+ temp := dy2*(wx0-x0);
+ yd += temp div dx2;
+ rem := temp mod dx2;
+ if (yd > wy1) or (yd = wy1) and (rem >= dsx) then exit;
+ xd := wx0;
+ e += rem;
+ if (rem >= dsx) then begin Inc(yd); e -= dx2; end;
+ end;
+
+ if (y1 > wy1) then
+ begin
+ // clip at bottom
+ temp := dx2*(wy1-y0)+dsx;
+ term := x0+temp div dy2;
+ rem := temp mod dy2;
+ if (rem = 0) then Dec(term);
+ end;
+
+ if (term > wx1) then term := wx1; // clip at right
+
+ Inc(term); // draw last point (it is ok to inc here, as `term` sign will be changed later
+ //if (term = xd) then exit; // this is the only point, get out of here
+
+ if (sty = -1) then yd := -yd;
+ if (stx = -1) then begin xd := -xd; term := -term; end;
+ dx2 -= dy2;
+
+ result := true;
+end;
+
+
// ////////////////////////////////////////////////////////////////////////// //
// you are not supposed to understand this
// returns `true` if there is an intersection, and enter coords
// ////////////////////////////////////////////////////////////////////////// //
// no callback: return `true` on the nearest hit
-function TBodyGridBase.traceRay (const x0, y0, x1, y1: Integer; cb: TGridRayQueryCB; tagmask: Integer=-1): ITP;
+function TBodyGridBase.traceRayOld (const x0, y0, x1, y1: Integer; cb: TGridRayQueryCB; tagmask: Integer=-1): ITP;
var
ex, ey: Integer;
begin
- result := traceRay(ex, ey, x0, y0, x1, y1, cb, tagmask);
+ result := traceRayOld(ex, ey, x0, y0, x1, y1, cb, tagmask);
end;
// no callback: return `true` on the nearest hit
// you are not supposed to understand this
-function TBodyGridBase.traceRay (out ex, ey: Integer; const ax0, ay0, ax1, ay1: Integer; cb: TGridRayQueryCB; tagmask: Integer=-1): ITP;
+function TBodyGridBase.traceRayOld (out ex, ey: Integer; const ax0, ay0, ax1, ay1: Integer; cb: TGridRayQueryCB; tagmask: Integer=-1): ITP;
const
tsize = mTileSize;
var
end;
+// ////////////////////////////////////////////////////////////////////////// //
+function TBodyGridBase.traceRay (const x0, y0, x1, y1: Integer; cb: TGridQueryCB; tagmask: Integer=-1): ITP;
+var
+ ex, ey: Integer;
+begin
+ result := traceRay(ex, ey, x0, y0, x1, y1, cb, tagmask);
+end;
+
+
+// no callback: return `true` on the nearest hit
+// you are not supposed to understand this
+function TBodyGridBase.traceRay (out ex, ey: Integer; const ax0, ay0, ax1, ay1: Integer; cb: TGridQueryCB; tagmask: Integer=-1): ITP;
+var
+ lw, sweepw: TLineWalker;
+ ccidx: Integer;
+ gw, gh, minx, miny: Integer;
+ cc: PGridCell;
+ px: PBodyProxyRec;
+ lq: LongWord;
+ f, ptag: Integer;
+ x0, y0, x1, y1, cx, cy, px0, py0, px1, py1: Integer;
+ lastDistSq, distSq, hx, hy: Integer;
+ firstCell: Boolean = true;
+ wasHit: Boolean;
+begin
+ result := Default(ITP);
+ tagmask := tagmask and TagFullMask;
+ if (tagmask = 0) then exit;
+
+ gw := mWidth;
+ gh := mHeight;
+ minx := mMinX;
+ miny := mMinY;
+
+ // make query coords to (0,0)-based
+ x0 := ax0-minx;
+ y0 := ay0-miny;
+ x1 := ax1-minx;
+ y1 := ay1-miny;
+
+ lw := TLineWalker.Create(0, 0, gw*mTileSize-1, gh*mTileSize-1);
+ if not lw.setup(x0, y0, x1, y1) then exit; // out of screen
+
+ sweepw := TLineWalker.Create(0, 0, 1, 1); // doesn't matter, just shut ups the compiler
+
+ lastDistSq := distanceSq(ax0, ay0, ax1, ay1)+1;
+
+ if mInQuery then raise Exception.Create('recursive queries aren''t supported');
+ mInQuery := true;
+
+ // increase query counter
+ Inc(mLastQuery);
+ if (mLastQuery = 0) then
+ begin
+ // just in case of overflow
+ mLastQuery := 1;
+ for f := 0 to High(mProxies) do mProxies[f].mQueryMark := 0;
+ end;
+ lq := mLastQuery;
+
+ ccidx := -1;
+ repeat
+ lw.getXY(cx, cy);
+ // check tile
+ ccidx := mGrid[(cy div mTileSize)*gw+(cx div mTileSize)];
+ // process cells
+ wasHit := false;
+ while (ccidx <> -1) do
+ begin
+ cc := @mCells[ccidx];
+ for f := 0 to GridCellBucketSize-1 do
+ begin
+ if (cc.bodies[f] = -1) then break;
+ px := @mProxies[cc.bodies[f]];
+ ptag := px.mTag;
+ if ((ptag and TagDisabled) = 0) and ((ptag and tagmask) <> 0) and (px.mQueryMark <> lq) then
+ begin
+ px.mQueryMark := lq; // mark as processed
+ if assigned(cb) then
+ begin
+ if not cb(px.mObj, ptag) then continue;
+ end;
+ // get adjusted proxy coords
+ px0 := px.mX-minx;
+ py0 := px.mY-miny;
+ px1 := px0+px.mWidth-1;
+ py1 := py0+px.mHeight-1;
+ // inside?
+ if firstCell and (x0 >= px0) and (y0 >= py0) and (x0 <= px1) and (y0 <= py1) then
+ begin
+ // oops
+ ex := ax0;
+ ey := ay0;
+ result := px.mObj;
+ mInQuery := false;
+ exit;
+ end;
+ // do line-vs-aabb test
+ sweepw.setClip(px0, py0, px1, py1);
+ if sweepw.setup(x0, y0, x1, y1) then
+ begin
+ // hit detected
+ sweepw.getPrevXY(hx, hy);
+ distSq := distanceSq(x0, y0, hx, hy);
+ if (distSq < lastDistSq) then
+ begin
+ lastDistSq := distSq;
+ ex := hx+minx;
+ ey := hy+miny;
+ result := px.mObj;
+ // if this is not a first cell, get outta here
+ if not firstCell then begin mInQuery := false; exit; end;
+ wasHit := true;
+ end;
+ end;
+ end;
+ end;
+ // next cell
+ ccidx := cc.next;
+ end;
+ // done processing cells; exit if we registered a hit
+ // next cells can't have better candidates, obviously
+ if wasHit then begin mInQuery := false; exit; end;
+ firstCell := false;
+ // move to next tile
+ until lw.stepToNextTile();
+
+ mInQuery := false;
+end;
+
+
end.