UIView坐标系-偏移和平移

-(void)didLoadMap:(NSNotification *)notification {

id region = [notification object];
ShapePolyline *polygon = [region polygon];

if ([notification name] == @\"MapsLoadingForState\") {

    // m_nBoundingBox is an array which contains the RAW northing and easting values for each subdivision.  [0] - west limit, [1] - south limit, [2] - east limit, [3] - north limit.

    // The code below, combined with the drawrect method in DrawMap.m (below) puts all the states on the map in precisely the right places, so for the state maps, it works just fine.

    CGFloat originX = ((polygon->m_nBoundingBox[0]-MASK_MIN_EASTING)*stateScaleMultiplier)+([mainContainerView frame].size.width/2);

    CGFloat originY = ((MASK_MAX_NORTHING-(polygon->m_nBoundingBox[3]))*stateScaleMultiplier)+[mainContainerView frame].origin.y;  
    CGFloat width = polygon->m_nBoundingBox[2] - polygon->m_nBoundingBox[0];
    CGFloat height = polygon->m_nBoundingBox[3] - polygon->m_nBoundingBox[1];

    CGFloat scaledWidth = width*stateScaleMultiplier;
    CGFloat scaledHeight = height*stateScaleMultiplier;
    UIColor *subViewColor = [UIColor colorWithRed:0.0 green:1.0 blue:1.0 alpha:0.0];

    stateMapView = [[DrawMap alloc] initWithFrame:CGRectMake(originX, originY, scaledWidth, scaledHeight)];
    [stateMapView setBackgroundColor:subViewColor];

    [stateMapView setStateScale:stateScaleMultiplier];
    [stateMapView setCountyScale:countyScaleMultiplier];  // Not actually needed.

    [stateMapView setClippingMask:polygon];
    UIColor *colorMask = [UIColor colorWithWhite:1.0 alpha:1.0];
    [stateMapView setForeground:colorMask];

    [states addObject:stateMapView];                      // Add the state map view to an array (for future use)
    [mapView addSubview:stateMapView];  // MapView is a UIView of equivalent size and shape as mainContainerView.

} else {

    // This is where the problems occur.  

    CGFloat originX = (polygon->m_nBoundingBox[0]-DIST_MIN_EASTING);  // 4431590 (raw data)
    originX *= countyScaleMultiplier;  // 303.929108
    originX += ([mainContainerView frame].size.width/2);  // 815.929077

    CGFloat originY = (DIST_MAX_NORTHING-polygon->m_nBoundingBox[3]); 4328997 
    originY *= countyScaleMultiplier;  // 296.893036
    originY -= [mainContainerView frame].origin.y;  // 340.893036

    CGRect frame = [stateMapView frame];  // Dummy variable created for watches in the debugger.  x=856.237183, y=332.169922 width=34.3800087, height=28.7534008

    // When I was invoking DrawMap.h and the included drawrect method, the county map would easily be displayed in the right place, as you can see by the values above.

    // This is where I think the problem is.  The X value is WAY off as far as I can tell.
    originX -= frame.origin.x; // -40.3081055 
    originY -= frame.origin.y; // 8.72311401

    CGPoint countyOrigin = CGPointMake(originX,originY);

    // Translate the county\'s origin so it is relative to the origin of stateMapView, not MainContainerView (doesn\'t work)

    [stateMapView addCountyMap:[region polygon] withColor:winner translatedBy:countyOrigin];
    [stateMapView setNeedsDisplay];
}

- (void)drawRect:(CGRect)rect {

// Set up

for (int i=0;i<[countyMaps count];i++) {

    // Draw the polygon.

    [[countyColors objectAtIndex:i] setFill];

    [self drawPolygon:[countyMaps objectAtIndex:i]
           usingScale:stateScale
         translatedBy:CGPointMake([[countyTranslations objectAtIndex:2*i] floatValue],
                                  [[countyTranslations objectAtIndex:2*i+1] floatValue])]; 

}

// Set the blend mode to multiply

CGContextSetBlendMode(context, kCGBlendModeMultiply);

// Draw a path with clippingMask

[[UIColor colorWithWhite:1.0 alpha:1.0] setFill];
// CGPoint translate = CGPointMake(0,0);

[self drawPolygon:clippingMask usingScale:stateScale translatedBy:CGPointMake(0,0)];

}

-(void)drawPolygon:(ShapePolyline *)aPolygon usingScale:(float)mapScale translatedBy:(CGPoint)trans {

for (int j=0;j<[aPolygon numParts];j++) {

    UIBezierPath *path = [UIBezierPath bezierPath];

    [path setLineJoinStyle:kCGLineJoinRound];

    int startIndex = [[[aPolygon m_Parts] objectAtIndex:j] intValue];
    int endIndex = [aPolygon numPoints];

    CGPoint startPoint;
    [[[aPolygon m_Points] objectAtIndex:startIndex] getValue:&startPoint];

    startPoint.x *=mapScale;
    startPoint.y *=mapScale;

    startPoint.x -= trans.x;
    startPoint.y -= trans.y;

    [path moveToPoint:startPoint];


    if (j+1 != [aPolygon numParts]){ 

        endIndex = [[[aPolygon m_Parts] objectAtIndex:j+1] intValue];
    }

    for (int k=startIndex+1; k<endIndex; k++)
    {
        CGPoint nextPoint;
        [[[aPolygon m_Points] objectAtIndex:k] getValue:&nextPoint];

        nextPoint.x *= mapScale;
        nextPoint.y *= mapScale;

        nextPoint.x -= trans.x;
        nextPoint.y -= trans.y;

        [path addLineToPoint:nextPoint];

    }
    [path closePath];
    // [path stroke];
    [path fill];
}

}