Working with the Camera - Essentials of Interactive Computer Graphics - page 402

class CDrawHandler : public UWBD3D _ WindowHandler {

public :
.

Source file.
DrawOnlyHandler.h/cpp
files in the WindowHandler
folder of the D3D _ CameraLib
project.

A: void DrawGraphics();
.
protected :
B: UWBMFC _ UIWindow m _ window;

// The drawing area

};

void CDrawHandler::DrawGraphics() {
.
BeginDraw();
C: LoadViewXform();
LoadProjectionXform();
D: D3DXMATRIX identity; D3DXMatrixIdentity(&identity);
m _ pD3DDevice->SetTransform( D3DTS _ WORLD, &identity);
m _ pD3DDevice->Clear( ... );
E: theApp.GetModel().DrawModel();
EndDrawAndShow();

}

Listing 15.9. The CDrawHandler class of Tutorial 15.1.

different classes to support programmability. The resulting matrix is the
view matrix M w 2 e , as defined by Equation (14.4). The final step of com-
puting the view matrix at label A1c involves rotations to support mouse
interactions. We will examine this last step in Tutorial 15.3.

• Projection matrix (label B). The LoadProjectionXform() function com-
putes the projection matrix projMat (at label B1) and loads this matrix into
the PROJECTION matrix processor (at label B2). The projMat is computed
by the ComputeProjectionMatrix() function, where at label B1a we ac-
cess the view frustum parameters from the UWB _ Camera class, and at label
B1b we call the D3DXMatrixPerspectiveFovRH() function to compute
the actual perspective projection matrix. Notice that as above, we are call-
ing the exact same function as that label C1 in Listing 14.4. Once again, the
UWBGL library merely reorganizes graphics API function calls to support
abstractions.