Is there any way to create a variable-width stroke on a drawn path? I need to imitate a pen pressure effect (without using a tablet). Can I do this by changing some properties of a stoke?
Thanks in advance
usually dont like just posting links! But this is what you need A Smooth and Responsive Drawing Application in AS3
It determines the thickness by the mouse speed, you can obviously change that to fit your needs
Related
After Effect has the possibility to apply the a Bezier Surface over an image.
However we want to achieve that affect with AS3.
We can use DisplacementMapFilter, using a mapBitmap for each frame for the bezier effect..
How can we generate each of those bitmaps?
The only information that after effect gives are the 12 control points for 12 key frames each one.
How can we with that information generate those mapBitmap that the DisplacementMapFilter operation requests?
Maybe after effect has another information that we are missing?
Thanks in advance.
I'm asuming you're trying to come up with something like this: http://fatlinesofcode.philipandrews.org/2011/02/20/warping-bitmaps-with-a-bezier-surface/
Displacement map filter has limitations that would make this difficult.
The trick is to break up the image into triangles and warp these triangles along the bezier lines/surface you like. The more triangles you use the smoother the resulting image.
this is a good place to start : http://www.flashandmath.com/advanced/p10triangles/index.html
here is a more advanced example (without code) http://www.miaumiau.cat/2010/03/simple-surface-editor/ that is using bezier curves
more code here also: http://wonderfl.net/c/rFOlY
you can try looking up more resources with drawTriangles and distort keywords
I've been searching for answer for about 2 hours now and I haven't found my desired answer. My question is, Is it possible, and how, to draw a circle-shaped texture, so that outside the circle, texture would be transparent, is it even possible?
Thanks in advance! This site has been a great help so far!
The easiest way is to open a program like Photoshop and make an image with an alpha-channel. That means: Start with a completely transparent image and draw a circle on it. Then save it as .png
You can then just load it in your game and render it using a SpriteBatch. It (or better your graphics card) knows how to handle the alphachannel and will keep everything but the circle completely invisible.
This way you do not have to manipulate any pixmaps at runtime and you are not limited to simple shapes like circles.
If the portion of the texture you want to see in the circle is not meant to change during execution, the easiest way is to open Photoshop, make what you want, export it as an image and then load it in a Texture or a Sprite object in your code.
But this can also be done at runtime, via OpenGL using a Stencil test. This is the only solution if the portion displayed in the circle will have to be alterable during execution.
pixmap use this link if u are using other than .png format for your images
Apart form it if you are using png images then just draw the cirlce. Outside the circle will remain transparent.
By default, adding a Stroke to a Shape in WPF / WinRT XAML creates an outline that is centered around the edges, meaning that half of the outline is outside the shape. But I need to create a shape with stroke und no fill that has the same silhouette as the shape with fill and no stroke. Is there an easy way to change the stroke so that the whole outline is inside?
I could create an OpacityMask that covers the inverted shape, but OpacityMasks are not supported in WinRT XAML. I could also create a smaller shape via inward polygon buffering (An algorithm for inflating/deflating (offsetting, buffering) polygons), but I was hoping for a simpler solution, e.g. a simple property to change the stroke to "inside".
I've really been trying to come up with an answer to this one. Over and over every attempt has some type of limitation. I'm afraid the answer is, you cannot do this - not with dynamic vectors at least. You can always create an image to simulate it. But that sucks.
I'm working on a 2d tile based HTML5 canvas application and I would like to know what kind of special effects I can apply to the images as their being drawn ( context.drawImage(...) ). The only trick I've come across is modifying the canvas.globalAlpha value. This leaves some color from the previous frames, creating a blurring or dazed effect if things on the canvas object are moving from frame to frame.
Is there something for rendering images that is comparable to setting the context.fillStyle to an ARGB value for primitive shapes?
Is there a multiply mode? ie: multiply the image pixel color by the destination color. This could be used for primitive lighting. (I've toyed around with context.globalCompositionOperation but didn't find anything interesting)
Are there any other cool effects you've come across?
NOTE: I don't want to use WebGL for this application, and it's a game. That means it's realtime and I can't modify each pixel with javascript code because that takes too long. (although I could probably do that when the player dies and nothing is moving on the screen anymore)
Canvas doesn't provide any predefined effects.
To manipulate the image shape you can use matrix transformations.
To manipulate the image pixels and colors you should use getImageData method - http://www.whatwg.org/specs/web-apps/current-work/multipage/the-canvas-element.html#pixel-manipulation.
Then use google to find algorithms to apply some effects like swirl, blur, emboss etc.
I have a basic paint application on a canvas, and I want to make a drawing-border and by that create a stencil. In other words, I want to make a shape, and then I want the user to be able to draw only inside it, even when he tries to draw outside.
Do you have any idea how can i do it?
thanks
This can be achieved by making a clipping region. The basic idea is that there is a path on the canvas that all drawing is constrained to.
Make the shape, and instead of calling stroke() or fill(), call clip()
If you don't quite get how clipping regions work, there are a few examples around.