October 2011
1 post
5 tags
Random-Position in Iterator Module
Setting objects in iterator modules “freely” or “random” can be a little hard, because you can get “Iterator Variables”, that are only linear scales of the single objects. For example you get variables like 0, 1, 2, 3… or variables between 0..1. Setting your objects with that value you can get easily linear distributions, but nothing by random.
There is a simple quick method to place the...
September 2011
1 post
4 tags
Simple Scene Manager
This is a simple, but effective approach, to make a scene manager in Quartz Composer patches. The Boolean Demultiplexer works as input source. You put in the number of the scene you want to show. The type of output is “Boolean”, so only 1 or 0. This enables or disables the connected scenes. The bool-values are connected the enable-input of the patches. So if not used, than the patch...
June 2011
1 post
3 tags
Sample and Hold: Temporary save a value
This patch saves a value in the sample and hold module. In that case pressing the “key-down” triggers the saving of the value. You can feed any other changing signal into the sampling input.
May 2011
2 posts
5 tags
Video-Framebuffer with Queue Module
This is how to build a simple “Framebuffer”, using the Queue-module: The video-input is feed into the Queue-module. The Queue Size set the length of the framebuffer-delay. To get the delayed image, we use the Structure Index Member module. Set the Index to “0” (zero) to get the frame, that is delayed by the Queue Size value. Of cause you also have access to all other structure-members from...
Edit Core Image Filter Code in Quartz Composer
If you want to write Core Image Filters, you will use the Core Image Filter module in Quartz Composer. Click on the Core Image Filter Module, open the Preferences Panel, go to the Settings drop down. There you got the code. Notice the additional options like “Edit Filter Function” (that will open another window with editable code). “Show Advanced Input Sample Functions”...
April 2011
4 posts
HOW DO I FORCE PATCHES TO EXECUTE?
While learning how to use patches, it is handy to use tooltips to investigate what outputs are produced given specific inputs. The problem comes when the tooltip results don’t seem to change whatever the inputs are set as.
As compositions are executed ‘from graphics back to the logic’, patches don’t execute unless they are connected (either directly or through other...
6 tags
Simple Debugger / Text-Console in Quartz Composer
This is how you can build yourself a simple text-console like debugger. You use a Image with String module and connect it to a Sprite or Billboard renderer. The string-input of the Image with String is where you feed your debug-values.
3 tags
Where do I edit the GLSL-Shader-Script?
If using the GLSL Shader Module, it can be hard to find the actual shader script to view and edit. Where to find it? You have to click on the Patch Inspector, than on the GLSL Shader. Then in the Patch Inspector itself select “Settings” in the drop-down menu. There is the editor, where the GLSL-Script is edited.
3 tags
Get Color from Image-Pixel
This is how to use a color from an image-pixel as background-color. This patch uses Clear, Image Pixel and RGB Color. The values of Pixel X and Pixel Y in Image Pixel are useful to use int, although parameters can also be float.