Transformation

To add scale, rotation and translation to a sample program:

Start with the project you created in Vector Load and Save.

 

1.

Add this local variable under L_INT nRet; in the WndProc function:

VECTORPOINT Point;

 

2.

Add these cases under the WM_COMMAND case:

case WM_CHAR:

      switch( wParam )

      {

      case 'x':

      case 'X':

      case 'y':

      case 'Y':

      case 'z':

      case 'Z':

         // get current rotation value

         L_VecGetRotation ( &Vector, &Point );

         Point.x += ( wParam == 'x' || wParam == 'X' ) ? 5.0 : 0;

         Point.y += ( wParam == 'y' || wParam == 'Y' ) ? 5.0 : 0;

         Point.z += ( wParam == 'z' || wParam == 'Z' ) ? 5.0 : 0;

         // set new rotation value

         L_VecSetRotation ( &Vector, &Point, NULL, NULL, 0 );

         InvalidateRect( hWnd, NULL, FALSE );

         break;

 

      case '+':

      case '-':

         // get current scale value

         L_VecGetScale ( &Vector, &Point );

         Point.x += ( wParam == '+' ) ? 0.1 : -0.1;

         Point.y += ( wParam == '+' ) ? 0.1 : -0.1;

         Point.z += ( wParam == '+' ) ? 0.1 : -0.1;

         // set new scale value

         L_VecSetScale ( &Vector, &Point, NULL, NULL, 0 );

         InvalidateRect( hWnd, NULL, FALSE );

         break;

      }

      break;

 

   case WM_KEYDOWN:

      switch( wParam )

      {

      case VK_UP:

      case VK_DOWN:

      case VK_LEFT:

      case VK_RIGHT:

         // get current translation

         L_VecGetTranslation ( &Vector, &Point );

         if( wParam == VK_LEFT ) Point.x -= 1.0;

         if( wParam == VK_RIGHT ) Point.x += 1.0;

         if( wParam == VK_UP ) Point.y += 1.0;

         if( wParam == VK_DOWN ) Point.y -= 1.0;

         // set new translation value

         L_VecSetTranslation ( &Vector, &Point, NULL, 0 );

         InvalidateRect( hWnd, NULL, FALSE );

         break;

}

break;

 

3.

Compile and run the demo.

4.

Select File/Open… from the program menu. Browse to C:\Program Files\LEAD Technologies\LEADTOOLS EVAL 15\Images\random.dxf and click OK.

5.

Now you should be able to rotate the vector drawing around any axis using the x, y and z keys on your keyboard and scale up and down using the + and – keys.