Things related to drawing graphics on screen. More...

Collaboration diagram for Graphics:

Classes
class	Color
	color in RGB space, with optional alpha More...

class	Font
	font for text drawing and measuring (GUI Only) More...

class	GraphicsManager
	Used to create and track ports (GUI Only) More...

class	Image
	A bitmap image that can be blitted onto the screen. More...

class	ImageStrip
	bitmap image containing a number of frames that can be blitted onto the screen More...

class	ISpriteDrawHelper
	helper for drawing sprite overlays and add-on effects More...

class	Offset
	offset within a 2D coordinate system More...

class	Point
	point for 2D coordinate system More...

class	Port
	area in which drawing is done, a viewport (GUI Only) More...

struct	PortDrawEvent
	a port needs to be redrawn (GUI Only) More...

struct	PortResizedEvent
	a port has been resized (GUI Only) More...

class	Quad
	4 point polygon in 2D system More...

class	Rect
	Rectangle for 2D coordinate system. More...

class	ResourceManager
	used for loading resources More...

class	RotatedRect
	rectangle with rotation for 2D coordinate system. More...

class	Vector
	vector (magnitude and direction) within a 2D coordinate system. More...

Variables
const	action_DrawPortComplete = 43
	eventType_SpriteLayer action: all drawing for every SpriteLayer has completed More...

const	action_ErasePort = 40
	eventType_SpriteLayer action: about to start drawing each SpriteLayer More...

const	action_PostDrawLayer = 42
	eventType_SpriteLayer action: completed rendering for a particular SpriteLayer More...

const	action_PreDrawLayer = 41
	eventType_SpriteLayer action: about to render a particular SpriteLayer More...

Detailed Description

Things related to drawing graphics on screen.

Class Documentation

class pdg::ISpriteDrawHelper

helper for drawing sprite overlays and add-on effects

Warning: API Stability: 1 - Experimental. This API was introduced recently and gotten little or no real use. It may change or be removed in future versions. It may not be completely implemented and may be missing important pieces of functionality. Please try it out and provide feedback.

Implement this interface to do extra drawing stuff for a specific Sprite then start using it by calling the sprite's setDrawHelper() method. You can only have one Sprite Draw Helper attached to a particular sprite for normal drawing (before the sprite would normally draw) and one for post draw (after the sprite has been drawn)

For those coding in Javascript, there is an implementation of ISpriteDrawHelper that maps a function definition to the draw call. So to create a helper:

var myHelper = new pdg.ISpriteDrawHelper(function(sprite, port) {
                console.log("in my sprite draw helper for " + sprite );
                var r = sprite.getLayer().layerToPortRect(sprite.getFrameRotatedBounds());
                port.fillRect(r, "black");
                port.frameRect(r, "white");
                return false;  // don't let sprite draw itself (ignored for post draw)
});
mySprite.setDrawHelper(myHelper);

If you need something more complex, you can also use classify to create a new Javascript class that derives from pdg.ISpriteDrawHelper, and it will call the draw() method of your class. For example:

classify(pdg.ISpriteDrawHelper, 'MyDrawHelperClass', function() {
                def('draw', function(sprite, port) {
                                console.log("MyDrawHelperClass.draw(" + sprite + ")" );
                                return true;  // let sprite draw itself (ignored for post draw)
                });
});
mySprite.setDrawHelper( new MyDrawHelperClass() );

Your Custom Function:

As you can see from the examples above, your Sprite Draw Helper function (or draw() method) will be called with two parameters, and return a boolean:

Parameters

sprite	the Sprite that is being drawn
port	the Port where the sprite should be drawn

Returns: true if the normal Sprite drawing should happen; or false if the normal Sprite drawing should be skipped. This return result only applies when called for pre-draw. If the helper is installed for as a post-draw helper, using setSpritePostDraw(), then the return result is ignored.

See Also: Sprite.setDrawHelper()

struct pdg::PortDrawEvent

a port needs to be redrawn (GUI Only)

Generated by the GraphicsManager whenever it is time to redraw a Port. All drawing calls should be done during the handling of a eventType_PortDraw.

{ 
    emitter: {},       // the emitter that generated this event
    eventType: 24,     // the event type (eventType_PortDraw)
    port: {},          // the port that needs to be redrawn
    frameNum: 12897    // how many times this event has been generated for this port
}

Note: these events are never generated in a non-GUI build, such as the PDG Node.js plugin

See Also: eventType_PortDraw; Port; GraphicsManager

struct pdg::PortResizedEvent

a port has been resized (GUI Only)

Generated by the GraphicsManager whenever a Port is resized or when the device orientation is changed.

{ 
    emitter: {},       // the emitter that generated this event
    eventType: 15,     // the event type (eventType_PortResized)
    port: {},          // the port that was resized
    screenPos: 0       // one of the screenPos_ constants, in this case screenPos_Normal
}