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I am using Inkscape and I know how to use transparency within the image, but I am annoyed that the background of the workspace in Inkscape is white. I searched through a lot of settings, but had no luck.
How do I get the workspace checkered like in GIMP?
The white workspace is really bothersome if you design something in white
You can change the background color in Inkscape by changing the document properties (in the File menu).
In particular, you can check 'Checkerboard background' to show the checkerboard if the background is set to transparent.
A quite ugly solution is to design your own checker background and have it as locked bottom layer :) Im doing something similar when im fiddling around with iOS icons or items that will be on a background.
Also as Juve mention you could try out the grids property.
First of all, a hint on transparency. If you export images with transparency for example to PDF (for printing), they are converted to bitmaps inside the PDF or produce unwanted results. Export to non-vector formats should be fine. I suggest to avoid transparency, usually there is a way to mimic transparency, e.g., by just using a light gray for shadows. Also don't use blur effects; similar problems with PDF export.
Now to the checkboard:
It's not possible, one workaround would be to add full page sized box and choose black checker board as fill. Put this box on a separate layer and lock the layer. You might also lighten that box up using one of the filters. Unfortunately this board won't adapt when zooming.
Maybe not the solution, but a related option would be the grid (press #). This is not behind your drawing but in front. It can help you with positioning. Maybe you were looking for this?
Related
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I'm trying to create a mask out of a custom shape. I tried it with image masking and the result is given below. While my desire result is not exactly.
Using this Mask Image
The visual effect that I want to have:
Can anyone provide some hints on how can I achieve my desire effect.
What you have achieved via masking is working correctly. Masking works on alpha channel, transparent area vs visible area and images you posted in your question show exactly that.
Masking won't be enough for the effect you want to achieve. You need to experiment with CIFilter api.
Check out cifilter.io that shows a few examples of how these are supposed to look like. You might want to check out the source code for the same.
If you run this iOS project in Xcode, it provides a very easy way to browse and choose which effect is the closest to what you want to achieve.
Good luck!
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I have an image as background of an ios app.
I want to make that image blurred using the iOS7 blur effect.
How can I achieve that? Minimum iOS version support of my iOS app is 6.0.
Your image will be in a UIImageView.
You can use this code...
self.theImageView.alpha = 0.5;
just set the alpha to whatever you want.
EDIT
From the comments you are actually looking for the iOS 7 blur effect.
This is very different from setting transparency.
What you are looking for is the category available from here https://developer.apple.com/downloads/download.action?path=wwdc_2013/wwdc_2013_sample_code/ios_uiimageeffects.zip
You will need to download the category then when you set the background just blur the image before putting it into the background pattern.
There is difference between transperency and translucency.
You can adjust transperency by using 'alpha' property as mentioned by fogmeister.
This will give you somewhat similar results.
AFAIK there is no direct API to apply translucency effect on image. Alternatively You can alter the image in external image editor tool eaisily and use it in your application.
Note : For image to have translucent effect, you need to have another image/text behind it.
set your imageView alpha value t 0.4 to 0.6
or
if you want dynamic blurred image background like below
FXBlurView
Simple Process:
Use a png file as background image.
Set this image's transparency level using photoshop.
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I want to display audio meters on the iPad consisting of many small green, red or black rectangles. They don't need to be fancy but there may be a lot of them. I am looking for the best technique to draw them quickly. Which of the following techniques is better: text atlas in CALayers or OpenGLES or another?
Thank you for your answers before the the question was closed for being too broad. Unfortunately I couldn't make the question narrow because I didn't know which technology to use. If I had known the answer I could have made the question very narrow.
The fastest drawing would be to use OpenGLES in a custom view.
An alternative method would be to use a texture atlas in CALayers. You could draw 9 sets of your boxes into a single image to start with (0-8 boxes on), and then create the 300 CALayers on screen all using that as their content. During each frame, you switch each layer to point at the part of the texture atlas it needs to use. I've never done this with 300 layers before, so I don't know if that may become a problem - I've only done it with a half dozen or so digits that were updating every frame, but that worked really well. See this blog post for more info:
http://supermegaultragroovy.com/2012/11/19/pragma-mark-calayer-texture-atlases/
The best way to draw something repeatedly is to avoid drawing it if it is already on the screen. Since audio meters tend to update frequently, but most of their area stay the same, because audio signals are relatively smooth, you should track what's drawn, and draw only the differences.
For example, if you have drawn a signal meter with fifty green squares in a previous update, and now you need to draw forty eight green squares, you should redraw only the two squares that are different from the previous update. This should save you a lot of quartz calls.
Postpone rendering to the point where it's absolutely necessary, i. e. assuming you're drawing with CoreGraphics, use paths, and only stroke/fill the path when you have added all the rectangles to it.
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I'm not sure if this is the best forum for this, because it's not a programming question per se, but here goes.
I am the developer for an iOS application, and we contracted the design out to a third-party. They delivered to us a massive PhotoShop file with all of the the individual pieces of artwork done on individual layers, at double resolution. To get the artwork into XCode, my workflow is as follows:
Show only the layers containing a particular unit of artwork
Select all
Copy Merged
Create New image (fortunately, the dimensions are taken care of automatically)
Paste
Deselect pasted layer and delete Background, to preserve transparency
Save image as x.psd
Save copy as x#2x.png
Set image size to 50% of original dimensions
Save copy as x.png
Discard changes
This app is pretty large, so it's quite tedious to do this process for every little image. I'm not very Photoshop savvy, so I'm wondering if there is a better way. It seems to me that it should be easy enough to combine steps 3-11 into one macro or script or something. The only thing that changes in each iteration over these steps is the output name. Any suggestions?
Normal workflow is exactly as you described. You can write a Photoshop script to do the layer exporting and Apple provides an Automator tool that will allow you to resize those graphics from 2x down 50%. Great tutorial here. This can help get your graphics to scale quickly.
There are solutions to automate what your trying to accomplish. This video tutorial allows you to take your PSD or PNG and port it into an Xcode with all of the layers properly placed in a view for you, create view controllers, and segues.
Disclaimer - I am associated with the JUMPSTART Platform as mentioned in the video.
You can script Photoshop with Javascript and I've written scripts in the past to perform similar series of steps, it wasn't too hard to figure out even for someone like me who'd never written any Javascript before. Photoshop also has 'Actions' which are like macros and you can probably do something simple like this with Actions as well but it's not something I've personally tried. Check out the Adobe docs on scripting Photshop: Adobe Photoshop Scripting.
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I have an iphone app with a picture of a face in the uiimage. I want to only change the eye color on the face by tapping on a button or tapping on a color wheel. Can you give me some help in what code I would need.
I would suggest taking a look at OpenCV. It works quite well on iOS devices, the main code comes with examples on how to build iOS applications and there is a lot of material on how to do eye detection and from there you should be able to change the colors.
Keep in mind this is not a simple task and you could accomplish with a easier thing. But you could learn a lot and there are tons of good resources around this topics.
If you want to do something faster, you might be able to just detect the touch on the UIView(enable user interaction) and present a color picker, after the color has been presented you could create a simple view on top of the image that has a circle with the color that was selected. It would be crappy, but might be a good idea to do a simple simple prototype.