view.md

Module view

Package view provides 4 modules:

• transform - basic module
• node - interface for drawing objects
• resolver - calc full transform matrix
• camera - node for using as camera

Module transform

interface Transform

methods:

• @property mat4 matrix() const; - you must implement in your realisation of Transform interface. This method must return transform matrix from local coord system to global.

• protected final static mat4 getMatrix( const(Transform) tr ); - returns identiny matrix if tr is null, and tr.matrix otherwise.

class SimpleTransform : Transform

implement matrix

    @property
    {
        mat4 matrix() const { return mtr; }
        void matrix( in mat4 m ) { mtr = m; }
    }

class TransformList : Transform

fields:

• Transform[] list
• Order order = Order.DIRECT - can be Order.REVERSE

methods:

• @property mat4 matrix() const - return result of multiplication of list matrix by order.

class CachedTransform : Transform

protected fields:

• mat4 mtr - cached matrix
• Transform transform_source

methods:

• void setTransform( Transform ntr ) - set new transform source and recalc
• void recalc() - set mtr as transform_source.matrix if transform_source isn't null, identity otherwise.

Module node

interface Node : Transform

methods:

• @property mat4 matrix() const - need implement (Transform) - local to parent transform matrix
• @property const(Node) parent() const - needs for resolving full transform matrix
• final @property vec3 baseX() const - base X vector of coord sys
• final @property vec3 baseY() const - base Y vector of coord sys
• final @property vec3 baseZ() const - base Z vector of coord sys
• final @property vec3 offset() const - offset in parent system

Module resolver

class Resolver

public methods:

• mat4 opCall( const(Node) obj, const(Node) cam ) const - calc full transform matrix from obj coord system to cam coord system

Module camera

class Camera: Node

protected fields:

• Node _parent

public fields:

• Resolver resolver - for full transform matrix calculation
• Transform projection - present projection matrix
• Transform transform - present view matrix

public methods:

• this( Node parent=null ) - set parent and create new resolver
• mat4 resolve( const(Node) obj ) const - return full transform matrix
• mat4 opCall( const(Node) obj ) const - return full transform matrix with projection if it isn't null
• @property mat4 matrix() const - return transform.matrix if it isn't null, identity otherwise
• @property const(Node) parent() const - return _parent

class LookAtTransform : Transform

public fields:

• vec3 pos=vec3(0) - point from which looks
• vec3 target=vec3(0) - point where looks
• vec3 up=vec3(0,0,1) - up direction

public methods:

• @property mat4 matrix() const - return lookAt transform matrix

abstract class ResolveTransform : Transform

protected fields:

• Resolver resolver

public methods:

• void setResolver( Resolver rsl )
• abstract @property mat4 matrix() const

class LookAtNodeTransform : ResolveTransform

use Node instead of vec3

public fields:

• Node center - as pos
• Node target
• Node up

public methods:

• @property mat4 matrix() const - return lookAt transform matrix

class PerspectiveTransform : Transform

public fields:

• float fov = 70
• float ratio = 4.0f / 3.0f
• float near = 1e-1
• float far = 1e5

public methods:

• @property mat4 matrix() const - return perspective projection matrix

class SimpleCamera : Camera

Camera with LookAtTransform as transform and PerspectiveTransform as projection

protected fields:

• LookAtTransform look_tr
• PerspectiveTransform perspective

public methods:

• this( Node parent=null ) - create new LookAtTransform and PerspectiveTransform objects and sets to transform and projection

public propertyes (meaning same in LookAtTransform and PerspectiveTransform):

• void fov( float val )
• float fov() const
• void ratio( float val )
• float ratio() const
• void near( float val )
• float near() const
• void far( float val )
• float far() const
• void pos( in vec3 val )
• vec3 pos() const
• void up( in vec3 val )
• vec3 up() const
• void target( in vec3 val )
• vec3 target() const

Using example

class SomeDrawObject : Node
{
    protected mat4 mtr;

    ...

    const @property
    {
        mat4 matrix() { return mtr; }
        const(Node) parent() { return null; } // always no parent, world coord sys
    }
}

auto cam = new SimpleCamera;
auto obj = new SomeDrawObject;

auto tr = cam(obj);

// and now you can
someAPI_setTransform( tr );
someAPI_drawObject( obj );