So i made simple drawing script
This is what u can draw with it :D
So anyway my question is i wan't to make Erase Tool i already made one but it only removes 1 pixel at time instead i want to make hexagon thing and able to scale it up i just need formula to do that or simple explanation no script required
I want to be look like here I can just fill up pixels but i am not sure about how to deal with scaling part.
Looks like I'm extremely late, but if anybody else needs this help in the future, here's the solution.
You can simply loop for every pixels (a for loop for each y coordinates [as j] embedded in a for loop for each x coordinates [as i]).
Then for each of those loops, check the distance from the cursor's current position to the pixel located at (i, j), and if it's smaller than the chosen radius, change the pixel for a blank one.
The recommended way of checking the distance between two pixels in Roblox would be something like so:
(Vector2.new(x1, y1) - Vector2.new(x2, y2)).magnitude
Related
In GeoGebra, you can easily construct scenes with the GUI and the tools available in the Graphics view. I now have two functions and created some objects around them using that tools (Their intersection point, a circle tangent to both etc.). The whole depends on 5 parameters I defined as sliders for testing.
Now I want to know the coordinates of the point. It is defined as Intersect[l, h] which doesn't help me. I can access its coordinates too (0.8, 3.98) but I want to know how to calculate them depending on the parameters. (I'd expect it to be something like (3a, 7+b-2a)). I know GeoGebra can do this because it must have done it internally to be able to draw the whole image. But I don't know how to access this information.
If you want to get the current position of a Point P you can use the x and y commands. These will update whenever the position of P changes so that you don't have to recalculate where the point should be by hand.
I am working on creating a way for a user to move polygons on screen and change their shape by dragging their corner vertices. I then need to be able to re-draw those modified polygons on other devices - so I need to be able to get final positions of all vertices for all polygons on screen.
This is what I am currently doing:
I draw polygons using UIBezierPath for each shape in the override of the drawRect function. I then allow user to drag them around the screen by applying CGAffineTransformMakeTranslation function and the x and y coordinate deltas in touchedMoved function override. I have the initial control points from which initial polygons are drawn (as described here). But once a path instance is moved on screen, those values don't change - so I am only able to get initial values.
Is there something built - in in the Core Graphics framework that will allow me to grab a set of current control points in a UIBezierPath instance? I am trying to avoid keeping track of those points manually. I will consider using other ways to draw if:
there is a built - in way to detect if a point lies within that polygon (such as UIBezierPath#contains method
A way to easily introduce constraints so user can't move a polygon out of bounds of the superview (I need the whole polygon to be visible)
A way to grab all points easily when user is done
Everything can run under 60fps on iPhone 5.
Thanks for your time!
As you're only applying the transform to the view/layer, to get the transformed control points from the path, simply apply that same transform to the path, and then fetch the control points. Something like:
UIBezierPath* copiedPath = [myPath copy];
[copiedPath applyTransform:[view transform]];
[self yourExistingMethodToFetchPointsFromPath:copiedPath];
The way that you're currently pulling out points from a path is unfortunately at the only API available for re-fetching points from an input UIBezierPath. However - you might be interested in a library I wrote to make working with Bezier path's much simpler: PerformanceBezier. This library makes it significantly easier to get the points from a path:
for(NSInteger i=0;i<[path elementCount];i++){
CGPathElement element = [path elementAtIndex:n];
// now you know the element.type and the element.points
}
In addition to adding functionality to make paths easier to work with, it also adds a caching layer on top of the existing API to make the performance hit of working with paths much much smaller. Depending on how much CPU time you're spending on UIBezierPath methods, this library will make a significant improvement. I saw between 2x and 10x improvement, depending on the operations I was using.
Ok, I'm not quite sure if this is something I can ask here so no need to shoot me down. Just tell me and i'll delete the question :)
I had this idea of making my own clock using a touch screen and program it myself.
While thinking about this I thought of all these different styles to show the current time.
Of all the styles I came up with there was one that I found the most fun which is a clock displaying the time Rorschach style. And no not just a random smudge and guess what time it is but more like Rorschach in watchmen.
He has a mask with inkblots that constantly change shape (really cool if you ask me).
So what I had in mind is inkblots that change shape according to the digit it represents.
When the time changes
12:49:58 -> 12:49:59 the 2nd second digit will transform from 8 -> 9.
So now back to the original problem:
Before attempting to get this type of clock running I want to try to give a blob a certain shape and make it transform into another shape.
I searched on google but without any luck so I was hoping there was someone here that could point me in the right direction for making a random blob and transform it into another shape in an animation.
For example:
Draw square -> animate to circle
Any tips and tricks are welcome :)
In order to get the most simpliest animation of digit transformation you could store all posible digits in one image (verticaly) and then only partially show that image in your component. So when you want to do transformation between one digit to another you simply slide the image up and down.
Now if you are using FireMonkey you could create a 3D viewport and inside it create a cylindical object onto which will you render your texture with digits. So now you only rotate the cilinder in order to show the corect digit.
Do anybody know how to apply transformation to sprite without opportunities of SpriteBatch.Draw() method ?
(Update from comments)
This is what I need: I have a circle sprite. This picture contains shadows. I need to stretch this circle (make ellipse) and rotate it, but I want the shadow does not change its position into ellipse. Rotation and scaling change every frame. I think it's possible with matrix transformation
The matrix passed into SpriteBatch.Begin is applied last. Using this is the only way to achieve a scale operation following a rotate operation through SpriteBatch (assuming your scale is non-uniform).
The downside is that, if the scale of each sprite is different, you will have to start a new batch for each.
Your other option is to write your own sprite batcher - but that seems a bit drastic.
Thanks! I've found solution, but it is very slowly =(
this.displayMatrix =
Matrix.CreateTranslation(-(new Vector3(Position, 0))) *
Matrix.CreateRotationZ(1) *
Matrix.CreateScale(new Vector3(new Vector2(1f, 2f), 1)) *
Matrix.CreateTranslation((new Vector3(Position, 0)));
Can anyone share a sample code to draw a non-rectangular part of a picture in delphi canvas?
You're looking for GDI paths. Start here, which explains what paths are in this context, and provides links on the left to explain the functionality available with them.
Google can turn up lots of examples of using paths in Delphi. If you can't find them, post a comment back here and I'll see what I can turn up for you.
Your question is pretty vague. But I suspect what you are looking for is clipping regions. Read up on them. Set the clipping region on the target device to the shape you want, and then draw the image onto the device. Only the part of the image that would be within the clipping region will be drawn.
Canvas.Ellipse(0, 0, 10, 20); // not a rectangle
I use so called runlists for this feature (generalized shapes and blitting them). I've seen them called warplists too. A shape is encoded as a runlist by defining it as a set of horizontal lines, and each line is two integer values (skip n pixels,copy n pixels).
This means you can draw entire lines, leaving you with only "height" draw operations.
So a rectangle is defined (the first "skip" pixels from top level corner to the left corner (xorg,yorg). The rectangle is width_rect wide, and width_pixels goes a line further. width_pixels can be wider than the width of the picture (alignment bytes)
(yorg*width_pixels+xorg , width_rect),
(width_pixels-width_rect , width_rect),
(width_pixels-width_rect , width_rect),
(width_pixels-width_rect , width_rect),
..
..
This way you can make your drawing routines pretty generic, and for simple, regular shapes (rects, circles) it takes only minor math to precalculate these lists. It simplified my shape handling enormously.
However I draw directly to bitmaps, not to canvasses, so I can't help with that part. A primitive that efficiently draws a row, and a way to extract a row from a graphic should be enough.