There are three basic ways to move a path in Raphael.
If that path has a fill image that has PNG transparency, and you need IE8 (VML), all three are flawed.
JSBin demo
If you use a simple transform...
path1.animate({transform: 't20,100'},1000);
...then in IE8, the png transparency in the fill breaks and translucent pixels turn black. Edges become pixelated and ugly, and depending on the image you might get a scuffy black outline around the translucent edge of the image. Not good, and there doesn't seem to be any reliable way to fix this after the event.
Sometimes, inconsistently, the background image also doesn't stay relative to the element (more on that below).
If you animate the path attribute, for example like this:
path2.animate({path: Raphael.transformPath( path2.attr('path'), 't100,20') },1000);
...IE8 doesn't wreck the image background. However, the fix for making background images relative to the element not the paper does not work with this method (and various ways I've tried to bodge it using improved background image offset with an additional "M-20,-20" element don't seem to work), and I can't find any way to make that work either.
Also, just having lots of transformations on the go can break the delicate IE8 bug the background image fix depends on in VML mode, causing the background to move. This seems to be inconsistent - with the JSBin above, in IE8, sometimes they all move, sometimes only the top one moves.
If you use translate...
path3.translate(42,42);
...the results are the same as transform (presumably both use the same translate functions).
With Raphael image elements, it's possible to fix this broken alpha by applying opacity with the transform in an attr or animate call. This doesn't work with path fills. Also, turning off the fill and resetting it from the original URL string doesn't remove the broken alpha contamination. You can see this in this demo.
So, I'm looking for a way to move a Raphael path that has a background image that has PNG transparency that a) keeps the image relative to the element, consistently and b) doesn't wreck the PNG transparency in IE8 by turning partial transparency into pixelated black.
Similar problems occur with any form of transformation - such as scale, rotate etc.
I can't find any good answer to this: the closest I've found is an ugly but functional workaround for IE8 transform (wrapped in if(Raphael.type=='VML')s so you don't spoil things for real browsers):
Before doing any transform to anything that has an alpha transparency PNG / pattern fill, remove the pattern fill (path.attr({fill:'none'});), storing the fill setting like path.data('fill',path.attr('fill'));
After the transform, asynchronously (e.g. wrapped in setTimeout(function(){ })) re-apply the fill e.g. path.attr({fill: path.data('fill')});
The crucial thing seems to be: the fill must not be applied when the transform occurs, else it'll be ruined forever, even if you remove and re-apply it. Be careful with the timing on this - it mustn't be possible for the fill to re-apply before the transform completes (e.g. watch out for race conditions with animations or other async processes).
If you're animating a transform, your options seem to be to either:
Clear the fill before the animation, just accept that there will be no fill while the animation takes place, and re-set in a callback after the animation completes
Implement your own animation handler than removes and re-applies the fill before and after every frame (this, of course, risks being a performance nightmare).
Related
So I have an instanced scene that is supposed to be the child of a colour rect in my tree. I want to randomly generate the nodes, but I also want parts of the view to be cut off if the texture no longer is above the main section. I know you can render nodes below their parents, but I don't know if stopping part of them from rendering is physically possible.
In this image I want the bottom circle to remain the same, but the top circle to not show anything above the dark purple box
This is the node tree in the editor
Is there any way to do this directly, or am I gonna have to use a viewport of some variety?
I believe what you want is to set rect_clip_content to true on the ColorRect (or whatever Control). Making invisible any part of its children outside of it.
From Godot's documentation:
bool rect_clip_content
Enables whether rendering of CanvasItem based children should be clipped to this control's rectangle. If true, parts of a child which would be visibly outside of this control's rectangle will not be rendered.
If what you want is the opposite, perhaps you can use z_index to have something render on top, occluding the parts you don't want visible.
There is also a trick you can use with lights (including 2D lights):
Make a light that matches the area you want things to be visible.
Set a custom material that will be transparent by default, but visible on the light pass. The simpler way to do this is to set the light_mode of the material to "Light Only". You could also do it with a custom shader instead.
Making something disappear with light, in 2D, is impossible. In 3D, you can use flags_use_shadow_to_opacity. That is how you make a shadow catcher.
But, there is one more trick: you can use a mask. This should give you full control of when to show or hide things. So, if none of the above solutions works for you, use a mask. I have an explanation in a different answer. See also: How to crop sprite in a non-rectangular form?.
Mighty Mochi Games recently (2022-03-30) made a compilation of the different approaches in video form: Mask Methods Collection - Godot 3.x - 2D
.
is it possible to create a stroke with a dynamic width with SVG? I want to achieve a Calligraphy look like here, here or here.
Is this even possible? It seems customization of strokes in SVG is fairly limited. Even gradients in strokes seem to be non-trivial (see here).
There is a proposal to add into SVG standard a mechanism, that does exactly what you want:
http://www.w3.org/Graphics/SVG/WG/wiki/Proposals/Variable_width_stroke
http://lists.w3.org/Archives/Public/www-svg/2013May/0041.html
There's even an example implementation available here:
https://rawgit.com/birtles/curvy/master/index.html
It is, however, by no means official and we cannot be even sure it'll ever be.
Until then you'll need to stick to Bezier curves and object filling:
You can also use calligraphic fonts, for example - Tangerine available on Google CDN:
This approach requires less work since you don't need to draw everything from scratch, but then again, using third party fonts leaves you with little control over the final result.
You can't dynamically adjust the stroke of a path element. However you could draw a path, use a fill color on it instead of stroke, then double back upon the letters at a slight distance away from the original line.
Also, if you are using the SVG on the web then you can use css fonts on text elements. There are some pretty good cursive fonts that you can use for free... just check google web fonts.
I'm building a Container using code and now I want to set the Styleusing one UnselectedStyle from the Resource Editor.
I'm doing this because, I don't find the way to add a LinearBackground color and a RoundBorder to my Container. When I put the two properties to the Style, the background color has gone.
So I finally add this Style using the UIManager.getInstance().addThemeProps(String name ThemeFromResource); and later the setUIID(String nameStyle). Is working fine...my Containergets the Style, but the app lose the navigation, the back Commandhas gone.
How can do this? I would like to do with my first way...creating the lineargradient and the border and adding it to the style, but I don't find the way.
I would strongly suggest against doing that.
Border's override other forms of background, round border tries to respect some of them but is REALLY inefficient about that. It effectively draws the background on a mutable image then draws the round border on another mutable image, gets the RGB for both and performs a NOT operation to crop the background into a round image. This (as you might understand) is REALLY expensive in terms of performance, while the image is then cached it is still expensive in the longer term.
You should use image borders which are MUCH faster.
I am trying to rotate a circle image using jquery rotate plugin. But, I observe that the circle image appears to be oscillating about it's center while rotating. Something like a linear movement.
In IE7, it's pretty much observable. In Chrome/Firefox, if you zoom a bit, this wobbling issue can be observed.
I tried to rotate the image using Raphael library too. But still, the circle was wobbling.
Then I rotated the image with a c# program to see if the problem is with the browsers' graphic engine. But even here this issue is observed. I even took various images to see if the circle was imperfect. But, all the images show this behavior.
Can this be happening because of anti aliasing? Or, is it just an optical illusion?
If not, then what else can be the reason?
I am using jqueryrotate plugin rotate method to do this. $('#circleimg').rotate(Position);
Check this jsFiddle. Btw, this is the kind of source code you can include yourself in your question to make answering it easier for others.
http://jsfiddle.net/KyJzQ/
I used this rotate plugin since you did not specify which one you used.
HTML
<img id="circleimg" src="http://i.imgur.com/KgUDClr.png">
<img id="circleimg2" src="http://i.imgur.com/sK4qP6z.png">
JAVASCRIPT
var rot = 0;
window.setInterval(function() {
$('#circleimg').rotate(rot);
$('#circleimg2').rotate(rot);
rot += 1;
},
5
);
I think the circle you've provided is not actually a perfect circle, hence the tiny "oscillations" you see.
I added another circle that I rendered myself. If you zoom in closely enough you will see jagged pixels moving around the edge of my circle, but I don't see any way around this since the jQuery plugin is not actually re-rendering the image. I don't see any of the "oscillating" you mention in my circle.
This issue is more about vector art than it is about programming. Get a nice vector graphics program and render the nicest circle you can. Even the one I made is not really that good. Or use HTML5 and canvas to draw dynamically, rather than moving a static image around.
I've placed an image on top of a div. I'm trying to blend the image into the div (The div is a solid color). In Google Chrome, it looks great! The colors blend perfectly. In IE 7, however, the colors show a hard line even though they should be the same color! After some examination (a print screen put into paint.net to check the actual RGB values), IE 7 is actually lightning up my image.
The blend has to look seamless. Google Chrome was fine with this thus far. Any ideas why IE 7 wont display the color right?
The two browsers are using different rendering engines. There are minor differences between them in how they render graphics, particularly jpegs.
The differences are minor but unavoidable.
Most of the time it goes unnoticed; it only makes an appearance in cases like yours when you try to position it against an element with a solid background colour that is supposed to be the same.
You may be able to resolve the issue by using a different image format. Try saving the image as a PNG. PNGs tend to be rendered more accurately between the browsers than jpegs, so that might be enough to solve your problem.
If that doesn't solve your problem, you could try using PNGs alpha transparency feature to produce an image with a fade to transparent at the edge, and then overlap the background colour behind it. This will definitely give you a smooth transition, but is a bit more technical, so harder to achieve. It will also give you problems with older versions of IE (IE6 for sure, I think you'll be okay with IE7), as they had some major bugs with PNG transparency. (If this is an issue for you, there are work-arounds for this; google IEPNGFix for more)