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Change plot line thickness in ScottPlot

How can I change the plot line thickness in ScottPlot? And preferably also point thickness.
I've tried:
var plt = new Plot(1000, 500);
plt.AddScatter(times, temperatures, Color.Blue);
plt.LineWidth = 4;
But LineWidth apparently only works for signal plots (where AddSignal() is used instead of AddScatter()).

You can do this through the constructor:
plt.AddScatter(times, temperatures, Color.Blue, lineWidth: lineWidth, markerSize: markerSize)
Based on this example here: https://scottplot.net/cookbook/4.1/category/plottable-scatter-plot/#custom-lines
For what it's worth, setting LineWidth does work, but it looks like you tried to set the linewidth of the plotting window rather than the actual scatter plot. This should work better:
var plt = new Plot(1000, 500);
var scat = plt.AddScatter(times, temperatures, Color.Blue);
scat.LineWidth = 4;
scat.MarkerSize = markerSize;
If you need more, you might want to check out the ScatterPlot docs. The docs haven't been available for very long unfortunately, but now that they're here they're a great source: https://scottplot.net/doc/v4/api/ScottPlot.Plottable.ScatterPlot.html

Creating a box in UI image using line renderer not working

I'm planning to create a square inside UI image using line renderer but size is too small that you need to zoom In. but if its outside the UI image its working. Please see attached imaged below
the line renderer component is attached to redkey1spawn object.
Tried derHugo code it works but somehow it overshoots in the screen

Your problem is that the LineRenderer works with coordinates in Unity Units.
A Screenspace Overlay canvas has pixel size scaling so the width and height (in Unity units) match up with the width and height (in Pixels) of the Window.
→ since you add 4 points
0, 0, 0
2, 0, 0
2, -2, 0
0, -2, 0
in worldspace it means they actually on the canvas will use e.g. 2px, -2px, 0px → very small.
You could e.g. multiply the sizes by the height or width of the image/canvas.
private void Start()
{
var lineRenderer = GetComponent<LineRenderer>();
var image = GetComponentInParent<RectTransform>();
// get the Unity worldspace coordinates of the images corners
// note: to get the scales like that ofcourse only works
// if the image is never rotated!
var worlsCorners = new Vector3[4];
image.GetWorldCorners(worlsCorners);
var imageWorldSize = new Vector2(Mathf.Abs(worlsCorners[0].x - worlsCorners[2].x), Mathf.Abs(worlsCorners[1].y - worlsCorners[3].y));
var positions = new Vector3[lineRenderer.positionCount];
var pointnum = lineRenderer.GetPositions(positions);
for (var i = 0; i < pointnum; i++)
{
positions[i] = positions[i] * imageWorldSize.x;
}
lineRenderer.SetPositions(positions);
}
Note, however, I'm actually not even sure you will see this LineRenderer since it is not a UI component I'm pretty sure the ScreenSpace Overlay will make every Image etc always render on top of it.

Positioning Graphics draw

I'm trying to draw some polygons and lines usinng e.Graphics.DrawPolygon (or DrawLine). But I have a little problem specifying the coordinates where to draw. I am drawing onto a PictureBox using its Paint event. The elements draw correctly relatively to each other (creating the required final picture), but seem always to draw in the upper-left corner of the PictureBox. When creating the points to draw, when I just try to multiply the coordinates, it draws it at the same place but bigger (size is multiplied, instead of location coordinates).
Here is my code:
//some for loop
{
//getting the coordinates
Point toAdd = new Point((int)xCoord, (int)yCoord); // creating the point from originaly a double, here i tried to multiply..
tmpPoints.Add(toAdd); // tmpPoints is a List<Point>
}
points.Add(tmpPoints.ToArray()); //List<Point[]>
drawBuffer = points; //saving to a public List<Point[]>
points.Clear();
this.Invalidate();
here part of the pictureBox1_Paint method:
for (int i = 0; i < drawBuffer.Count; i++)
{
//some other stuff like deciding which color to use, not very important
Brush br = new SolidBrush(polyColor);
e.Graphics.FillPolygon(br, drawBuffer[i]);
brush.Dispose();
}
I have checked using breakpoint, the coordiinates are the same ratio (what was 100 pixels wide is still 100 pixels wide), they are at coordinates like x 3000 and y 1500, but it just draws itself in the upper-left corner. When i multiply the coordinates 3 times (see the code for the place where i multiplied), it draws at the same place but 3 times bigger (doesn't make sense after checking the coords...)
So, my question is - how do I set the location correctly, or is there any other way to do this?
Like this (I know, this is nonsense, just an example)
foreach(Polygon poly in e.Graphics)
{
poly.Location = new Point(poly.Location.X * 2, poly.Location.Y * 2);
}

When you multiply the coordinates of the points, they're scaled around the point (0, 0), the top-left corner of the canvas:
In order to scale it around its center (and I suppose you expected it to work this way), you need to calculate some kind of center of the polygon. For simplicity, it can be even an arithmetic mean of the coordinates, on X and Y axes respectively. If you already have the coordinates of the center, translate the coordinates of every point by a reversed vector made from the center coordinates (this is how it would look like if you drew it after this operation - the polygon's center is in the center of the coordinate system):
Now, do your scaling:
and move it back by the vector of polygon's center coordinates:

when you multiply
poly.Location = new Point(poly.Location.X * 2, poly.Location.Y * 2);
you are doing a stretch operation when you add
poly.Location = new Point(poly.Location.X + 50, poly.Location.Y +50); you are doing a translation operation.

If you want to shift everything without modifying the stored coords then just translate the graphics before drawing:
private void pictureBox1_Paint(object sender, PaintEventArgs e)
{
e.Graphics.TranslateTransform(100, 100); // shift the origin somehow
// ... draw the polygons as before ...
}

Having the Background or Camera "Scroll" based on charcter position

I'm working on an RPG game that has a Top-Down view. I want to load a picture into the background which is what the character is walking on, but so far I haven't figured out how to correctly have the background redraw so that it's "scrolling". Most of the examples I find are auto scrolling.
I want the camera to remained centered at the character until you the background image reaches its boundaries, then the character will move without the image re-drawing in another position.

Your question is a bit unclear, but I think I get the gist of it. Let's look at your requirements.
You have an overhead camera that's looking directly down onto a two-dimensional plane. We can represent this as a simple {x, y} coordinate pair, corresponding to the point on the plane at which the camera is looking.
The camera can track the movement of some object, probably the player, but more generally anything within the game world.
The camera must remain within the finite bounds of the game world.
Which is simple enough to implement. In broad terms, somewhere inside your Update() method you need to carry out steps to fulfill each of those requirements:
if (cameraTarget != null)
{
camera.Position = cameraTarget.Position;
ClampCameraToWorldBounds();
}
In other words: if we have a target object, lock our position to its position; but make sure that we don't go out of bounds.
ClampCameraToBounds() is also simple to implement. Assuming that you have some object, world, which contains a Bounds property that represents the world's extent in pixels:
private void ClampCameraToWorldBounds()
{
var screenWidth = graphicsDevice.PresentationParameters.BackBufferWidth;
var screenHeight = graphicsDevice.PresentationParameters.BackBufferHeight;
var minimumX = (screenWidth / 2);
var minimumY = (screnHeight / 2);
var maximumX = world.Bounds.Width - (screenWidth / 2);
var maximumY = world.Bounds.Height - (screenHeight / 2);
var maximumPos = new Vector2(maximumX, maximumY);
camera.Position = Vector2.Clamp(camera.Position, minimumPos, maximumPos);
}
This makes sure that the camera is never closer than half of a screen to the edge of the world. Why half a screen? Because we've defined the camera's {x, y} as the point that the camera is looking at, which means that it should always be centered on the screen.
This should give you a camera with the behavior that you specified in your question. From here, it's just a matter of implementing your terrain renderer such that your background is drawn relative to the {x, y} coordinate specified by the camera object.
Given an object's position in game-world coordinates, we can translate that position into camera space:
var worldPosition = new Vector2(x, y);
var cameraSpace = camera.Position - world.Postion;
And then from camera space into screen space:
var screenSpaceX = (screenWidth / 2) - cameraSpace.X;
var screenSpaceY = (screenHeight / 2) - cameraSpace.Y;
You can then use an object's screen space coordinates to render it.

Your can represent the position in a simple Vector2 and move it towards any entity.
public Vector2 cameraPosition;
When you load your level, you will need to set the camera position to your player (Or the object it should be at)
You will need a matrix and some other stuff, As seen in the code below. It is explained in the comments. Doing it this way will prevent you from having to add cameraPosition to everything you draw.
//This will move our camera
ScrollCamera(spriteBatch.GraphicsDevice.Viewport);
//We now must get the center of the screen
Vector2 Origin = new Vector2(spriteBatch.GraphicsDevice.Viewport.Width / 2.0f, spriteBatch.GraphicsDevice.Viewport.Height / 2.0f);
//Now the matrix, It will hold the position, and Rotation/Zoom for advanced features
Matrix cameraTransform = Matrix.CreateTranslation(new Vector3(-cameraPosition, 0.0f)) *
Matrix.CreateTranslation(new Vector3(-Origin, 0.0f)) *
Matrix.CreateRotationZ(rot) * //Add Rotation
Matrix.CreateScale(zoom, zoom, 1) * //Add Zoom
Matrix.CreateTranslation(new Vector3(Origin, 0.0f)); //Add Origin
//Now we can start to draw with our camera, using the Matrix overload
spriteBatch.Begin(SpriteSortMode.Immediate, BlendState.AlphaBlend, SamplerState.LinearClamp, DepthStencilState.Default,
RasterizerState.CullCounterClockwise, null, cameraTransform);
DrawTiles(spriteBatch); //Or whatever method you have for drawing tiles
spriteBatch.End(); //End the camera spritebatch
// After this you can make another spritebatch without a camera to draw UI and things that will not move
I added the zoom and rotation if you want to add anything fancy, Just replace the variables.
That should get you started on it.
However, You will want to make sure the camera is in bounds, and make it follow.
Ill show you how to add smooth scrolling, However if you want simple scrolling see this sample.
private void ScrollCamera(Viewport viewport)
{
//Add to the camera positon, So we can see the origin
cameraPosition.X = cameraPosition.X + (viewport.Width / 2);
cameraPosition.Y = cameraPosition.Y + (viewport.Height / 2);
//Smoothly move the camera towards the player
cameraPosition.X = MathHelper.Lerp(cameraPosition.X , Player.Position.X, 0.1f);
cameraPosition.Y = MathHelper.Lerp(cameraPosition.Y, Player.Position.Y, 0.1f);
//Undo the origin because it will be calculated with the Matrix (I know this isnt the best way but its what I had real quick)
cameraPosition.X = cameraPosition.X -( viewport.Width / 2);
cameraPosition.Y = cameraPosition.Y - (viewport.Height / 2);
//Shake the camera, Use the mouse to scroll or anything like that, add it here (Ex, Earthquakes)
//Round it, So it dosent try to draw in between 2 pixels
cameraPosition.Y= (float)Math.Round(cameraPosition.Y);
cameraPosition.X = (float)Math.Round(cameraPosition.X);
//Clamp it off, So it stops scrolling near the edges
cameraPosition.X = MathHelper.Clamp(cameraPosition.X, 1f, Width * Tile.Width);
cameraPosition.Y = MathHelper.Clamp(cameraPosition.Y, 1f, Height * Tile.Height);
}
Hope this helps!

Connecting two shapes together, Silverlight 2

I'm looking to connect or glue together two shapes or objects with a Line. These shapes will be generated dynamically, meaning I'll be calling a Web service on the backend to determine how many objects/shapes need to be created. Once this is determined, I'll need to have the objects/shapes connected together.
The method signature may look like this (similar to Visio's drawing capabilities):
GlueTogether(objButton1, objButton2);
I may need to get the position of each Rectangle shape or Button to determine where the starting Line point is. Then determine the second shape/objects position to draw the line.
Any help or suggestions would be great!

Use a Path or a Line below the shapes in stacking order or z index
Use instance.TransformToVisual() to get the transform of each shape
Use the transform to transform the centerpoint of each shape
Draw a line between the two centerpoints.
var transform1 = shape1.TransformToVisual(shape1.Parent as UIElement);
var transform2 = shape2.TransformToVisual(shape2.Parent as UIElement);
var lineGeometry = new LineGeometry()
{
StartPoint = transform1.Transform(new Point(shape1.ActualWidth / 2, shape1.ActualHeight / 2.0)),
EndPoint = transform2.Transform(new Point(shape2.ActualWidth / 2.0, shape2.ActualHeight / 2.0))
};
var path = new Path()
{
Data = lineGeometry
};

I am trying much the same, but instead of the line going from one centre to the other I want the lines to stop at the edge of the two shapes.
In particular I have arrows at the end of the lines, and the arrows need to stop at the bounds of the shapes instead of going inside/behind the shape to its centre.
My shape is a usercontrol with a grid and rectangle, and some labels and other stuff.
I can't find any methods that provide me with a geometry for the edge of the shape (which is a rounded rectangle).
I figured out a solution that uses the bounding box and intersection points to connect my elements by lines at their approximate edges, and it works well for me using arrow ended lines.
See Connecting two WPF canvas elements by a line, without using anchors?

Check this out: http://www.graphspe.com/Main.aspx#/Solution/graphviz-xaml-renderer
All you have to do is printf to a string and you get your Silverlight[2|3] diagram.
Ceyhun

In addition... Instead of connecting to the center point of your objects, I've modified the same code from Michael S. to:
var lineGeometry = new LineGeometry()
{
StartPoint = transform1.Transform(new Point(1 , b1.ActualHeight / 2.0)),
EndPoint = transform2.Transform(new Point(b2.ActualWidth , b2.ActualHeight / 2.0))
};
This will connect at the outer portions of each object.

I am using the above code to draw two buttons, I want a line between those two buttons, but all i get are two buttons that look like tiny circles and no line.
code:
Button b1 = new Button();
Button b2 = new Button();
canvas1.Children.Add(b1);
canvas1.Children.Add(b2);
Canvas.SetLeft(b1, 300);
var transform1 = b1.TransformToVisual(b1.Parent as UIElement);
var transform2 = b2.TransformToVisual(b2.Parent as UIElement);
var lineGeometry = new LineGeometry()
{
StartPoint = transform1.Transform(new Point(1, b1.ActualHeight / 2.0)),
EndPoint = transform2.Transform(new Point(b2.ActualWidth, b2.ActualHeight / 2.0))
};
var path = new Path()
{
Data = lineGeometry
};
canvas1.Children.Add(path);