CATiledLayer uses different set of tiles to handle different levels of zoom This example is exactly what we left from previous part of this tutorial. Based on some further logging I’ve added to the example project, I think the problem is this: The CATiledLayer has two render threads that. Let’s take a look at a CATiledLayer demo. I first ran across the CATiledLayer class when I was looking into a multithreaded, tiled.
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I started testing with full resolution photos on an iPad 1, and I found what the customer had discovered. The process of tiling the photo made it exxmple easy to exhaust memory on the device. Make those changes, then rebuild to check that everything compiles.
I have to use code to split the large image file into smaller cztiledlayer at runtime. It defaults to 0, meaning no additional magnified levels will be cached, and each incremental level will be cached at double the preceding level’s resolution.
Layer Player expands upon this usage by also drawing a path on top of the tiled layer background:. Notice that cstiledlayer underlying Quartz image data CGImage is assigned. An Apple support engineer provided me with a workaround: Tiling holds a lot of promise. I carefully prioritized generating tiles for the lowest level of detail first, so I would maximize responsiveness to the user.
CATiledLayer – Core Animation | Apple Developer Documentation
A customer contacted me telling me that the program was crashing. His PDF demo concisely illustrated how a CATiledLayer could be wired up and integrated into an application, and saved me no end of trouble. This line is a little peculiar. Here is how I’m getting the tiles from the large image: When invalidating a view backed by a CATiledLayer, a previous tile remains “stuck” and isn’t correctly invalidated.
This demo completely punts on one of the trickiest problems that would be encountered in a production implementation of CATiledLayer ; no effort is made to associate geometry with the proper tiles. Sign up using Facebook.
Pholio Coder’s Guide: Tiling Large Images
Things that were not immediately obvious to me. The layer’s contentsScale property defines the relationship between view space points and backing store pixels. I’m assuming it has something to do with the tile size and the zoom scale, but I really have no clue how to solve the problem.
Int The number of levels of detail maintained by this layer. As you might assume, setting rate to a negative number instructs playback to commence at that number times regular speed in reverse. Okay — that was a lot of ground to cover. CGSize The maximum size of each tile used to create the layer’s content. It’s fairly basic and cannot directly respond to user touches or even check catiledlayerr bounds of the scrollable layer, but it does cool things like preventing scrolling beyond the bounds ad infinitum!
One of the biggest challenges I faced writing Pholio was handling large images. I have the following:. Each defaults to 0, and that effectively preserves color value across all instances. Your challenge as a programmer: Remarks Okay — that was a lot of ground to cover. Based on some cayiledlayer logging I’ve added to the example project, I think the problem is this: The rendering of a tile can be expensive and can use the render thread for 10ms.
This seems to happen when the view is invalidated on catoledlayer main threadwhile at the same time, the tile render threads are still working on a previous version of the tile.
Any help would be great! The following function is a very slight re-write of the preexisting pathGroupsForTileView: The previous changes are not animated, and if isGeometryFlipped is not set to truethe positional geometry and shadow will be upside-down. After a few emails back and forth, I figured out why: In other words, an x value of 1 means the point is at the right edge of the layer, and a y value of 1 means the point is at the bottom edge of the layer.
Not familiar with trait collections?