Parallax Node is a special
Node type that simulates a parallax scroller.
What did you say? A para.. what? Yes, parallax Simply put you can consider
ParallaxNode to be a special effect that makes it appear that the position
or direction of an object appears to differ when viewed from different positions.
Simple every day examples include looking through the viewfinder and the lens of
a camera. You can think of many games that function this way, Super Mario Bros
being a classic example.
ParallaxNode objects can be moved around by a
and also manually by mouse, touch, accelerometer or keyboard events.
Parallax nodes are a bit more complex than regular nodes. Why? Because they
require the use of multiple nodes to function. A
ParallaxNode cannot function
by itself. You need at least 2 other
Node objects to complete a
As usual, in true Cocos2d-x fashion, a
ParallaxNode is easy to create:
// create ParallaxNode auto paraNode = ParallaxNode::create();
Since you need multiple
Node objects, they too are easily added:
// create ParallaxNode auto paraNode = ParallaxNode::create(); // background image is moved at a ratio of 0.4x, 0.5y paraNode->addChild(background, -1, Vec2(0.4f,0.5f), Vec2::ZERO); // tiles are moved at a ratio of 2.2x, 1.0y paraNode->addChild(middle_layer, 1, Vec2(2.2f,1.0f), Vec2(0,-200) ); // top image is moved at a ratio of 3.0x, 2.5y paraNode->addChild(top_layer, 2, Vec2(3.0f,2.5f), Vec2(200,800) );
OK, looks and feels familiar, right? Notice a few items! Each
Node object that
was added is given a unique z-order so that they stack on top of each other.
Also notice the additional 2
Vec2 type parameters in the addChild() call. These
are the ratio and offset. These parameters can be thought of as the ratio
of speed to the parent
It's hard to show a
ParallaxNode in text, so please run the example Programmer Guide Sample code to see this in action!