I'm using Embarcadero RAD Studio C++ builder XE7.
For a drawing function using the Windows GDI, I need to add a clip region to the device context of a canvas.
By testing my code, I noticed that sometimes the clipping region was smaller than the expected size. I searched why and I found a strange behavior of the OffsetRgn() function which lets me a little puzzled.
To apply the clip region, I use a code similar to the following:
std::unique_ptr<TBitmap> pBitmap(new TBitmap());
pBitmap->PixelFormat = pf32bit;
pBitmap->AlphaFormat = afDefined;
pBitmap->SetSize(60, 7);
TCanvas* pCanvas = pBitmap->Canvas;
::SelectClipRgn(pCanvas->Handle, NULL);
const TRect sourceRect = pCanvas->ClipRect;
HRGN pClipRegion = ::CreateRectRgn(50, -2, 60, 8);
::SelectClipRgn(pCanvas->Handle, pClipRegion);
const TRect intermediateRect = pCanvas->ClipRect;
const int deltaX = pCanvas->ClipRect.Left - 50;
const int deltaY = pCanvas->ClipRect.Top - (-2);
::OffsetRgn(pClipRegion, -deltaX, -deltaY);
::SelectClipRgn(pCanvas->Handle, pClipRegion);
const TRect finalRect = pCanvas->ClipRect;
NOTE written like this and out of his context, the above code does not really make sense, and I know it's illogical. Please do not judge its quality, this is not the purpose of my question. I gathered several excerpts that I grouped into an executable code putting the problem forward.
The hardcoded values are an example of values I get in my application when the problem occurs. If I execute the above code, I measure:
left = 0, top = 0, right = 60, bottom = 7 in sourceRect value
left = 50, top = 0, right = 60, bottom = 7 in intermediateRect value
left = 50, top = 0, right = 60, bottom = 6 in finalRect
I however expected that the bottom value should also be equals to 7 in finalRect, which is the canvas limit, as I only moved the region and nothing else. So why it's value become suddenly smaller than expected?
So I finally found the substance of the case. Based on this post:
Why does calling GetRgnBox on the result of GetClipRgn return a very different rect than GetClipRect?
The clip region is applied in logical units relatively to the canvas origin, whereas the clipping rectangle I tried to apply was measured in pixels from a [0, 0] origin.
As I incorrectly thought in my code that the origin was always [0, 0] for the both systems, the resulting region could be incorrect in several special cases, causing this strange shifting I sometimes noticed between the clipping really applied and which I expected.
Measuring the canvas origin with the GetWindowOrgEx() function highlighted the issue.
However for the above shown case, issue came because the clip region was moved by an offset of -2, taking so the value of -4 on top and 6 on bottom, which is then clipped to fit the canvas bounds while the clip region is applied, resulting to a clipping with value of 0 on top and 6 on bottom.
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I want to display a message, and close the window when the user clicks. This should happen when the circle reaches the bottom of the window. I'm not sure how to go about this, everything works fine until the circle passes the bottom of the window, the closing message doesn't pop up and the window doesnt close on click. I'm using the graphics.py graphics library from Zelle for Python. I'm a beginner in Python so my knowledge is very limited right now. My code is as follows:
from graphics import *
def q2a():
win = GraphWin("window",400,400)
win.setCoords(0,0,400,400)
win.setBackground("light grey")
#drawing circle
circle = Circle(Point(200,100),30)
circle.setFill("red")
circle.draw(win)
#text
message = Text(Point(200,200),"Click Anywhere to Begin")
message.draw(win)
#clicking
while True:
click = win.checkMouse()
if click:
message.undraw()
while circle.getCenter().getY() < 170:
dy=1
dx = 0
dy *=-.01
circle.move(dx,dy)
if circle.getCenter()== 0:
circle.undraw()
gameover = Text(Point(200,200),"Game Over - Click to Close")
gameover.draw(win)
win.checkMouse()
win.close()
q2a()
I believe the problem is simpler than you're making it. One problem is that this is an infinite loop:
while circle.getCenter().getY() < 170:
dy=1
dx = 0
dy *=-.01
circle.move(dx,dy)
As circle's Y center starts at 100 and decreases, so it's always less than 170 so this loop never finishes and any code beyond this point is never executed. Let's use the circle's radius, 30, instead so the circle stops when it sits on the bottom of the window.
Another issue is that I believe you're using checkMouse() when you really want getMouse(). Read the documentation about the difference between these two commands.
Here's my rework of your code (with some style tweaks.) I changed the -0.01 increment to -0.1 as I've no patience!
from graphics import *
RADIUS = 30
HEIGHT, WIDTH = 400, 400
CENTER = Point(HEIGHT / 2, WIDTH / 2)
def q2a():
win = GraphWin("window", HEIGHT, WIDTH)
win.setCoords(0, 0, HEIGHT, WIDTH)
win.setBackground("light grey")
# drawing circle
circle = Circle(Point(WIDTH / 2, 100), RADIUS)
circle.setFill("red")
circle.draw(win)
# text
message = Text(CENTER, "Click Anywhere to Begin")
message.draw(win)
# moving
win.getMouse()
message.undraw()
while circle.getCenter().getY() > RADIUS:
circle.move(0, -0.1)
# end game
circle.undraw()
gameover = Text(CENTER, "Game Over - Click to Close")
gameover.draw(win)
win.getMouse()
win.close()
q2a()
I am evaluating PdfSharp to create PDF documents. While comparing it with MigraDoc I figured that I had to multiply each position (x, y) or size by 1.25 to get the intended result. For example if I set the page margins to 2 cm without the correction, I get margins of roughly 1.6 cm.
page.TrimMargins = new TrimMargins
{
All = XUnit.FromCentimeter(2)
};
When I multiply 2 with 1.25 I get the intended 2 cm margins:
page.TrimMargins = new TrimMargins
{
All = XUnit.FromCentimeter(2 * 1.25)
};
Same is with font sizes. I have to multiply the size by 1.25 to get the same size as MigraDoc or even Word would print.
My system does not have a custom scaling or a text size other than 100% by the way (my guess was this could be the cause).
Can someone explain what's going on here?
Edit:
With the help of TomasH I found out that when printing without auto scaling the sizing was perfect. PdfSharp obviously creates PDF documents too large. When doing the same with MigraDoc the PDF is also a bit too large as I found out, but only on a much smaller scale. The question that remains is why the document is too large and what MigraDoc does to correct the PDF size.
Here is my complete test code that only gives the correct positioning and sizing with the correction factor:
using (PdfDocument document = new PdfDocument())
{
// Create an empty page size A4 with defined margins
PdfPage page = CreatePage(document);
using (XGraphics graphics = XGraphics.FromPdfPage(page))
{
const double sizeCorrectionFactor = 1.25;
// Define the page margins. They must be multiplied by 1.25 to be correct!?
page.TrimMargins = new TrimMargins
{
All = XUnit.FromCentimeter(2 * sizeCorrectionFactor)
};
// Draw a string. The font size needs to be multiplied by 1.25 to be correct!?
double x = 0;
double y = 0;
graphics.DrawRectangle(XPens.Black, XBrushes.White, 0, 0, page.Width, page.Height);
graphics.DrawString("PdfSharp Measure Demo", new XFont("Verdana", 20 * sizeCorrectionFactor), XBrushes.Navy, x, y, XStringFormats.TopLeft);
// Draw a rectangle. Position and size must be multiplied by 1.25 to be correct!?
x = XUnit.FromCentimeter(2 * sizeCorrectionFactor);
y = XUnit.FromCentimeter(2 * sizeCorrectionFactor);
double width = XUnit.FromCentimeter(5 * sizeCorrectionFactor);
double height = XUnit.FromCentimeter(5 * sizeCorrectionFactor);
graphics.DrawRectangle(XPens.Red, XBrushes.Silver, x, y, width, height);
}
string pdfFilePath = Path.GetTempFileName() + ".pdf";
document.Save(pdfFilePath);
Process.Start(pdfFilePath);
}
I found the answer: I got the meaning of the (not well documented) TrimMargins property wrong. Setting the trim margins obviously adds the size of the margins to the width or height of the page. This means if trim margins are set, the page size is too large and usually gets scaled down when displaying or printing it. I set 2 cm for the trim margins, making the page obviously 1.25 times too large. The solution is to let all trim margins be 0 and account for any desired page margins in the printing code instead.
I trying to do some Joint Tracking with kinect (just put a ellipse inside my right hand) everything works fine for a default 640x480 Image, i based myself in this channel9 video.
My code, updated to use the new CoordinateMapper classe is here
...
CoordinateMapper cm = new CoordinateMapper(this.KinectSensorManager.KinectSensor);
ColorImagePoint handColorPoint = cm.MapSkeletonPointToColorPoint(atualSkeleton.Joints[JointType.HandRight].Position, ColorImageFormat.RgbResolution640x480Fps30);
Canvas.SetLeft(elipseHead, (handColorPoint.X) - (elipseHead.Width / 2)); // center of the ellipse in center of the joint
Canvas.SetTop(elipseHead, (handColorPoint.Y) - (elipseHead.Height / 2));
This works. The question is:
How to do joint tracking in a scaled image, 540x380 for example?
The solution for this is pretty simple, i fugured it out.
What a need to do is find some factor to apply to the position.
This factor can be found takin the atual ColorImageFormat of the Kinect and dividing by the desired size, example:
Lets say i am working with the RgbResolution640x480Fps30 format and my Image (ColorViewer) have 220x240. So, lets find the factor for X:
double factorX = (640 / 220); // the factor is 2.90909090...
And the factor for y:
double factorY = (480/ 240); // the factor is 2...
Now, i adjust the position of the ellipse using this factor.
Canvas.SetLeft(elipseHead, (handColorPoint.X / (2.909090)) - (elipseHead.Width / 2));
Canvas.SetTop(elipseHead, (handColorPoint.Y / (2)) - (elipseHead.Height / 2));
I've not used the CoordinateMapper yet, and am not in front on my Kinect at the moment, so I'll toss out this first. I'll see about an update when I get working with the Kinect again.
The Coding4Fun Kinect Toolkit has a ScaleTo extension as part of the library. This adds the ability to take a joint and scale it to any display resolution.
The scaling function looks like this:
private static float Scale(int maxPixel, float maxSkeleton, float position)
{
float value = ((((maxPixel / maxSkeleton) / 2) * position) + (maxPixel/2));
if(value > maxPixel)
return maxPixel;
if(value < 0)
return 0;
return value;
}
maxPixel = the width or height, depending on which coordinate your scaling.
maxSkeleton = set this to 1.
position = the X or Y coordinate of the joint you want to scale.
If you were to just include the above function you could call it like so:
Canvas.SetLeft(e, Scale(640, 1, joint.Position.X));
Canvas.SetTop(e, Scale(480, 1, -joint.Position.Y));
... replacing your 640 & 480 with a different scale.
If you include the Coding4Fun Kinect Toolkit, instead of re-writing code, you could just call it like so:
scaledJoin = rawJoint.ScaleTo(640, 480);
... then plug in what you need.
I have a set of objects grouped with Raphael.set(). What I want to do is to move the whole set (change x and y coordinates) from one place to another.
How I can move the whole set as a single object?
What I found already is that when an .attr({X: newX, Y: newY}) is called every element from the set will be positioned on this coordinated which will result in piling all the elements in one place.
Edit: Refer to Rick Westera's answer as translate is now deprecated.
Use .translate(x, y), example:
var paper = Raphael('stage', 300, 300);
var set = paper.set();
set.push(paper.rect(0,0,30,50));
set.push(paper.circle(40,50,10));
set.push(paper.path("M 0 70 L 100 70"));
set.translate(100, 100);
http://jsfiddle.net/q4vUx/
Use transform('Tx,y') as translate is deprecated. For example:
var paper = Raphael('stage', 300, 300);
var set = paper.set();
set.push(paper.rect(0, 0, 100, 100));
set.push(paper.text(50, 50, "Foo"));
set.transform("T100,50");
Note that there are two types of translation:
'T100,50' will move the set 100px to the right and 50 down using the global axis.
't100,50' will do the same but using the set's local axis (ie. it depends on which way the set has been rotated).
This is what i'm using to reposition a set, in my case is a set of fonts returned by Paper.print() but i think it should work with any kind of set.
var glyphs = paper.print(0, 0, text, paper.getFont(font, 800), fontSize).hide();
glyphs.transform('...T' + [posx, posy] + 'R' + [angle, posx, posy]).show();
hope it helps.
Based on my experience with Zedgraph I could not set both of X and Y axes scale same to have a correct scatter graph! Assume we have a square grid of 10x10m cells in which each cell is a square shape 1x1m. when we try to draw points of such data, the output is not acceptable because each axis scaled to different scale. It is worse when we try to call Zoomall, then we find all points are fitted to chart area regardless their equal spacing!
I hope someone can help me to find a solution. Although Zedgraph is flexible library but this is a big fault!
perfectly aware, this q. is 9 years old, but still..
Have just encountered and solved the issue of presenting the graph in a square pane.
(It seems that was the OP question)
It's a bit "brute" and invokes redundant redraws, but gets the job done.
//"GraphWinFormsHost" is my ZGraph container
GraphWinFormsHost.SizeChanged += (sender, args) =>
{
//"IsEqualScale" is my property, indicating a square is needed
if(_ChartData == null || !_ChartData.IsEqualScale)
return;
_ZedGraphControl.GraphPane.Chart.IsRectAuto = true;
_ZedGraphControl.Refresh();
//here, the graph pane is redrawn according to available space
float x = _ZedGraphControl.GraphPane.Chart.Rect.X;
float y = _ZedGraphControl.GraphPane.Chart.Rect.Y;
float h = _ZedGraphControl.GraphPane.Chart.Rect.Height;
float w = _ZedGraphControl.GraphPane.Chart.Rect.Width;
float min = Math.Min(h, w);
_ZedGraphControl.GraphPane.Chart.Rect = new RectangleF(x, y, min, min);
};
Is Scale.IsAnyOrdinal true for any Axis.Scale's ?
ZedGraph appears to position nodes based on index offset rather than node value when the Scale.Type is set to AxisType.Text, Ordinal, DateAsOrdinal, or LinearAsOrdinal.
I recently had to solve the same problem. This is what has worked for me:
zg1.AxisChange();
if (myPane.XAxis.Scale.Max > myPane.YAxis.Scale.Max) {
myPane.YAxis.Scale.Max = myPane.XAxis.Scale.Max;
myPane.YAxis.Scale.Min = myPane.XAxis.Scale.Min;
myPane.YAxis.Scale.MajorStep = myPane.XAxis.Scale.MajorStep;
} else {
myPane.XAxis.Scale.Max = myPane.YAxis.Scale.Max;
myPane.XAxis.Scale.Min = myPane.YAxis.Scale.Min;
myPane.XAxis.Scale.MajorStep = myPane.YAxis.Scale.MajorStep;
}
zg1.AxisChange();
With the first call to AxisChange the control automatically calculate the correct values for my data. Then I copy the relevant parameters from one scale to the other one and apply the change.