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Crank Storyboard design guidelines
3 Crank Storyboard best practices
PHD API Reference
image. This will remove the transparency from the image. In most cases, the image
transparency will be replaced by the active foreground color. You could then change it to
an appropriate color for your background, or even combine it directly with the background
image first, and then flatten both together.
Fill or circle control replacements for graphics
Any graphics that are simple box or circle shapes of a single color should not be used as
images. Instead, remove the images from the project and replace them with Crank fill
controls. This will reduce both the size of the application and its memory usage while
running.
Polygon replacement for graphics
In some cases, some images could be replaced by Crank's polygon control. With the
polygon control, shapes can be drawn by specifying drawing points.
Even images that must be rotated in real-time can be replaced in this way.
The images below show screenshots from two slightly different Crank applications. One
screenshot is from an application using images for the four needles on the screen and the
other uses Crank's polygon control for each needle.
The image on the left uses the polygon controls for the four needles.
Layer alpha blending
Modifying an entire layer's alpha property to make it visible or invisible is a very
expensive operation and should be avoided.
It is better to have each image on the layer tied to a single alpha variable. That way, when
the variable is modified, all those elements will adjust their alpha. This is less demanding
on the device than blending the whole layer.
If using alpha to fade from one layer to another layer on a screen, it is more efficient to
create an additional screen and use the "Screen Fade" action to fade between the screens.
For example, for a logo screen that fades in, use an initial screen with a background color
and a second screen with the logo and background color. The initial screen can transition
to the logo screen using screen fade and it will have the same appearance as using the
alpha on the logo and fading it in.