hedgewars/uLandUtils.pas
author nemo
Mon, 10 Apr 2017 12:06:43 -0400
changeset 12218 bb5522e88ab2
parent 11709 1694b379c83f
child 12316 1b5a4807f8f4
permissions -rw-r--r--
bulk copy of latest physfs to our misc/libphysfs since this seems to fix an off-by-1 error reliably hit in readln read of 1 byte probably introduced in the addition of the buffered read. Whether this is excessive or whether libphysfs should even be maintained by us is another matter. But at least we shouldn't crash

unit uLandUtils;
interface

procedure ResizeLand(width, height: LongWord);
procedure InitWorldEdges();

implementation
uses uUtils, uConsts, uVariables, uTypes;

procedure ResizeLand(width, height: LongWord);
var potW, potH: LongInt;
begin
potW:= toPowerOf2(width);
potH:= toPowerOf2(height);
if (potW <> LAND_WIDTH) or (potH <> LAND_HEIGHT) then
    begin
    LAND_WIDTH:= potW;
    LAND_HEIGHT:= potH;
    LAND_WIDTH_MASK:= not(LAND_WIDTH-1);
    LAND_HEIGHT_MASK:= not(LAND_HEIGHT-1);
    cWaterLine:= LAND_HEIGHT;
    if (cReducedQuality and rqBlurryLand) = 0 then
        SetLength(LandPixels, LAND_HEIGHT, LAND_WIDTH)
    else
        SetLength(LandPixels, LAND_HEIGHT div 2, LAND_WIDTH div 2);

    SetLength(Land, LAND_HEIGHT, LAND_WIDTH);
    SetLength(LandDirty, (LAND_HEIGHT div 32), (LAND_WIDTH div 32));
    // 0.5 is already approaching on unplayable
    if (width div 4096 >= 2) or (height div 2048 >= 2) then cMaxZoomLevel:= cMaxZoomLevel/2;
    cMinMaxZoomLevelDelta:= cMaxZoomLevel - cMinZoomLevel
    end;
initScreenSpaceVars();
end;

procedure InitWorldEdges();
var cy, cx, lx, ly: LongInt;
    found: boolean;
begin
playHeight:= LAND_HEIGHT;
topY:= 0;

lx:= LongInt(LAND_WIDTH) - 1;

if WorldEdge = weNone then
    begin
    playWidth:= LAND_WIDTH;
    leftX := 0;
    rightX:= lx;
    EXIT;
    end;

ly:= LongInt(LAND_HEIGHT) - 1;

// find most left land pixels and set leftX accordingly
found:= false;
for cx:= 0 to lx do
    begin
    for cy:= ly downto 0 do
        if Land[cy, cx] <> 0 then
            begin
            leftX:= max(0, cx - cWorldEdgeDist);
            // break out of both loops
            found:= true;
            break;
            end;
    if found then break;
    end;

// find most right land pixels and set rightX accordingly
found:= false;
for cx:= lx downto 0 do
    begin
    for cy:= ly downto 0 do
        if Land[cy, cx] <> 0 then
            begin
            rightX:= min(lx, cx + cWorldEdgeDist);
            // break out of both loops
            found:= true;
            break;
            end;
    if found then break;
    end;

playWidth := rightX + 1 - leftX;
end;

end.