// compute bitmap for each slice (maybe do on demand?)
void compute_slice_images()
{
// construct bounding box and add buffer region
AxisAlignedBox3d bounds = Stack.Bounds;
double bufferMM = 1;
bounds.Expand(bufferMM);
Vector3d center = bounds.Center;
// will create a bitmap with this dots-per-inch
double dpi = 300;
double dpmm = dpi / Units.Convert(Units.Linear.Inches, Units.Linear.Millimeters);
CurrentDPIMM = (float)dpmm;
// pixel dimensions of image
int width = (int)(bounds.Width * dpmm);
int height = (int)(bounds.Height * dpmm);
// backgroun and object colors
SKColor bgColor = SkiaUtil.Color(0, 0, 0, 255);
SKColor objColor = SkiaUtil.Color(255, 255, 255, 255);
// function that maps from input coordinates to pixel space
Func <Vector2d, SKPoint> mapToSkiaF = (origPt) => {
origPt.y = -origPt.y; // [RMS] !!! flip Y here? if we don't do this the
// polylines we draw below don't match up. But maybe
// its the polylines that are wrong??
origPt *= dpmm;
origPt.x += width / 2; origPt.y += height / 2;
return(new SKPoint((float)origPt.x, (float)origPt.y));
};
foreach (PlanarSlice slice in Stack.Slices)
{
var bitmap = new SKBitmap(width, height, SkiaUtil.ColorType(), SKAlphaType.Premul);
IntPtr len;
using (var skSurface = SKSurface.Create(bitmap.Info.Width, bitmap.Info.Height, SkiaUtil.ColorType(), SKAlphaType.Premul, bitmap.GetPixels(out len), bitmap.Info.RowBytes)) {
var canvas = skSurface.Canvas;
canvas.Clear(bgColor);
using (var paint = new SKPaint()) {
paint.IsAntialias = false;
paint.Style = SKPaintStyle.Fill;
paint.Color = objColor;
foreach (GeneralPolygon2d poly in slice.Solids)
{
SKPath path = SkiaUtil.ToSKPath(poly, mapToSkiaF);
canvas.DrawPath(path, paint);
}
}
}
SliceImages.Add(bitmap);
}
}
void OnExpose(object sender, ExposeEventArgs args)
{
DrawingArea area = (DrawingArea)sender;
Cairo.Context cr = Gdk.CairoHelper.Create(area.GdkWindow);
int width = area.Allocation.Width;
int height = area.Allocation.Height;
AxisAlignedBox3d bounds3 = Stack.Bounds;
AxisAlignedBox2d bounds = (bounds3 == AxisAlignedBox3d.Empty) ?
new AxisAlignedBox2d(0, 0, 500, 500) :
new AxisAlignedBox2d(bounds3.Min.x, bounds3.Min.y, bounds3.Max.x, bounds3.Max.y);
double sx = (double)width / bounds.Width;
double sy = (double)height / bounds.Height;
float scale = (float)Math.Min(sx, sy);
// we apply this translate after scaling to pixel coords
Vector2f pixC = Zoom * scale * (Vector2f)bounds.Center;
Vector2f translate = new Vector2f(width / 2, height / 2) - pixC;
using (var bitmap = new SKBitmap(width, height, SkiaUtil.ColorType(), SKAlphaType.Premul))
{
IntPtr len;
using (var skSurface = SKSurface.Create(bitmap.Info.Width, bitmap.Info.Height, SkiaUtil.ColorType(), SKAlphaType.Premul, bitmap.GetPixels(out len), bitmap.Info.RowBytes))
{
var canvas = skSurface.Canvas;
canvas.Clear(SkiaUtil.Color(240, 240, 240, 255));
Func <Vector2d, Vector2f> xformF = (pOrig) => {
Vector2f pNew = (Vector2f)pOrig;
pNew -= (Vector2f)bounds.Center;
pNew = Zoom * scale * pNew;
pNew += (Vector2f)pixC;
pNew += translate + Zoom * Translate;
pNew.y = canvas.LocalClipBounds.Height - pNew.y;
return(pNew);
};
Func <Vector2d, SKPoint> mapToSkiaF = (pOrig) => {
Vector2f p = xformF(pOrig);
return(new SKPoint(p.x, p.y));
};
using (var paint = new SKPaint())
{
SKBitmap sliceImg = get_slice_image(currentLayer);
float w = sliceImg.Width / CurrentDPIMM, h = sliceImg.Height / CurrentDPIMM;
w *= Zoom * scale;
h *= Zoom * scale;
SKPoint sliceCenter = mapToSkiaF(Vector2d.Zero);
SKRect drawRect = new SKRect(
sliceCenter.X - w / 2, sliceCenter.Y - h / 2,
sliceCenter.X + w / 2, sliceCenter.Y + h / 2);
canvas.DrawBitmap(sliceImg, drawRect, paint);
paint.IsAntialias = true;
paint.Style = SKPaintStyle.Stroke;
PlanarSlice slice = Stack.Slices[currentLayer];
paint.Color = SkiaUtil.Color(255, 0, 0, 255);;
paint.StrokeWidth = 2;
foreach (GeneralPolygon2d poly in slice.Solids)
{
SKPath path = SkiaUtil.ToSKPath(poly, mapToSkiaF);
canvas.DrawPath(path, paint);
}
}
Cairo.Surface surface = new Cairo.ImageSurface(
bitmap.GetPixels(out len),
Cairo.Format.Argb32,
bitmap.Width, bitmap.Height,
bitmap.Width * 4);
surface.MarkDirty();
cr.SetSourceSurface(surface, 0, 0);
cr.Paint();
}
}
//return true;
}