Making a new character

For animations it is always good to allow the user community to create (and hopefully share) their own art and characters. Here, the advanced user will find the C++ based features of WCM extremely useful.

Note: This would also be a good time to review the “Simple Character Creation” tutorial, which is similar in content, but written from a somewhat different perspective, to the following paragraphs.

To make a completely new character in WCM, you must first define a new class derived from ICharacter or another class derived from ICharacter like ISpeakableCharacter , IHumanCharacter or IHumanCharacterSideView . As noted earlier these classes are incomplete, however they have many useful methods to register and work with characters. Some of them also have common parts declared but none of them have actual pictures assigned with parts. However to make these classes useful you need to derive a new class from them. In this example, we'll make a simple butterfly character by deriving a new class from ICharacter :

class Butterfly : public ICharacter

{

public :

Butterfly () : ICharacter ()

{

}

};

This class as currently written is still useless. It is basically just an outline and does not bring any new functionality to ICharacter . To make it a real character we need to do the following:

1. Declare all the desired parts (like Body, Head and so on). Some of the advanced interface classes already have some parts declared. For example ISpeakableCharacter has a Mouth part declared. IHumanCharacter and IHumanCharacterSideView have Mouth , RightArm , RightLeg , LeftLeg , Body , Head , RightEye , LeftEye and LeftArm declared. We are going to derive a new character from simplest ICharacter interface and will need to declare all the parts by ourselves.

2. Register character's dimensions and origin location using method Register in constructor.

3. Register all the parts in character's constructor specifying their default decal pictures, their coordinates relative to parent's origin (relative to character's origin if there is no parent) and part origin's coordinates using method RegisterPart .

4. If some parts have parents you must register parents using part's RegisterParent method

5. Register any additional decals using part's RegisterDecal method.

First of all let's find a couple of butterfly pictures with wings up and down. You can download these two images:

Download these images or create you own 300x300 pixels images and save them as "C:\\ButterflyCharacter\\butterfly1.svg" and "C:\\ButterflyCharacter\\butterfly2.svg"

These are two 300x300 pixels images. Let's use these dimensions as the dimension of our character. We'll use coordinates (175,145), relative to left upper corner, as the origin point. This is actually a middle of butterfly's body. Our character will have only one part – Body . It will also have 300x300 pixels dimensions and origin located at (175,145). The coordinates of Body's origin relative to character's origin will be at (0,0). (This is generally recommended for consistency between characters.) We'll use the first picture as the "DEFAULT" decal and register the second image as an additional decal:

class Butterfly : public ICharacter

{

public:

Part Body;

Butterfly () : ICharacter ()

{

// dimensions and the origin coordinates

Register ( 300, 300 , 175, 145 );

// coordinates of the part (0,0)

// and coordinates of the part's origin (175,145)

RegisterPart ( Body,

"C:\\ButterflyCharacter\\butterfly1.svg", 0 , 0, 175,

145 );

// we need to register one additional decal

Body.RegisterDecal ( "WINGS_DOWN",

"C:\\ButterflyCharacter\\butterfly2.svg" );

}

};

This is it! We have a new simple butterfly character created. We can move it using SetPos, we can change its body's decal and do other things.

We may also want our butterfly to fly. We can add an additional method to achieve this:

class Butterfly : public ICharacter

{

public:

…

void FliesTo ( double dX, double dY, double dDuration,

double dFlapDuration = 1 )

{

SetPos ( GetX (), GetY () ); // start control point

double dStartTime = GetTime (); // remember time

for ( int i=0; i<dDuration/dFlapDuration; i++ )

{

SetTime ( dStartTime + i * dFlapDuration );

Body.SetDecal ( "WINGS_DOWN");

SetTime ( dStartTime + i * dFlapDuration +

dFlapDuration / 2 );

Body.SetDecal ( "DEFAULT");

}

SetPos ( dX, dY ); // end control point

}

…

};

Here is a full example of using the character:

class Butterfly : public ICharacter

{

public:

Part Body;

Butterfly () : ICharacter ()

{

// dimensions and the origin coordinates

Register ( 300, 300 , 175, 145 );

// coordinates of the part (0,0)

// and coordinates of the part's origin (175,145)

RegisterPart ( Body,

"C:\\ButterflyCharacter\\butterfly1.svg", 0 , 0, 175,

145 );

// we need to register one additional decal

Body.RegisterDecal ( "WINGS_DOWN",

"C:\\ButterflyCharacter\\butterfly2.svg" );

}

void FliesTo ( double dX, double dY, double dDuration,

double dFlapDuration = 1 )

{

SetPos ( GetX (), GetY () ); // start control point

double dStartTime = GetTime (); // remember time

for ( int i=0; i<dDuration/dFlapDuration; i++ )

{

SetTime ( dStartTime + i * dFlapDuration );

Body.SetDecal ( "WINGS_DOWN");

SetTime ( dStartTime + i * dFlapDuration +

dFlapDuration / 2 );

Body.SetDecal ( "DEFAULT");

}

SetPos ( dX, dY ); // end control point

}

};

void Scene1 ()
{

Image Back ( "backgrounds/landscape.svg" );
Back.SetVisible ();

Butterfly MyButterfly;

MyButterfly.SetVisible ();

MyButterfly.SetPos ( 300, 100 );

MyButterfly.FliesTo ( -300, 100, 5 );

}

Please try to compile this movie to see a flying butterfly: