Combining Transformation Operators - Essentials of Interactive Computer Graphics - page 224

class CModel {

Source file. Model.h file
in the Model folder of the
D3D _ TranslateScaleObject
project.

.
// called by the slider bar event service routines
A: void SetTranslation( float x, float y);
// to update the m _ Transate/m _ Scale variables
void SetScale( float x, float y);
private :
.
// These are the t x and t y displacements
B: float m _ TranslateX, m _ TranslateY;
// These are the s x and s y scaling factors
float m _ ScaleX, m _ ScaleY;
C: UWB _ PrimitiveRectangle m _ Rectangle; // The rectangle

};

Listing 9.1. The CModel class of Tutorial 9.1.

void CModel::DrawModel() { Source file. Model.cpp

file in the Model folder of the
D3D _ TranslateScaleObject
project.

.
// the operators
A: D3DXMATRIX translate _ matrix, scale _ matrix, combined _ matrix;
// compute T ( t x , t y )
B: D3DXMatrixTranslation(&translate _ matrix, m _ TranslateX, m _ TranslateY, 0);
// compute S ( s x , s y )
D3DXMatrixScaling( &scale _ matrix, m _ ScaleX, m _ ScaleY, 1);
// M a = ST
C: D3DXMatrixMultiply(&combined _ matrix, &scale _ matrix, &translate _ matrix);
D: LPDIRECT3DDEVICE9 pDevice=UWBD3D _ GraphicsSystem::...GetD3DDevice();
// M W ← ST
pDevice->SetTransform(D3DTS _ WORLD, &combined _ matrix);
E: m _ Rectangle.Draw(lod, m _ DrawHelper);
.

}

Listing 9.2. The CModel::DrawModel() function of Tutorial 9.1.