EffectLayer for Pebble Smartwatch is a library that allows you to easily add special effects to your watchfaces or watch apps. You can even add multiple effects (up to 4 by default) to a single layer. But up until now you couldn’t easily remove added effect.
This feature could be useful when you need to add/remove an effect on the fly. For example user can choose to turn off or on color inversion from watchface config, so instead of creating/showing/destroying/hiding entire layer you can simple add/remove inversion effect.
Another use case is where you need to swap effects, for example remove 90-degree rotation clockwise and add 90-degree rotation counter-clockwise.
Well now you can, the library now has effect_layer_remove_effect function. What it does is simple removes last added effect. The effect showing in the demo above is achieved by this block of code:
switch (anim_count) {
case 0:
effect_layer_add_effect(effect_layer, effect_invert, NULL);
break;
case 1:
effect_layer_remove_effect(effect_layer);
effect_layer_add_effect(effect_layer, effect_rotate_90_degrees, (void *)true);
break;
case 2:
effect_layer_remove_effect(effect_layer);
effect_layer_add_effect(effect_layer, effect_mirror_vertical, NULL);
break;
case 3:
effect_layer_remove_effect(effect_layer);
break;
}
anim_count++;
if (anim_count == 4) anim_count = 0;
It is called every time animation movement is initiated for the layer. Layer is moved 4 times in this demo:
- On 1st call – inversion effect is added to the layer
- On 2nd call – last added effect (inversion) is removed and 90-degree rotation added
- On 3rd call – 90-degree rotation removed and vertical mirror effect is added
- On 4th call – effect is removed so now layer has no effects.
Combined the chain produced the effect shown in the animation above.
Ideally library should have “insert” and “remove_at” function to be able to insert and remove effects from arbitrary index (and not only the end of effect chain). Stay tuned.
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