ScreenToTerrain

This method matches a pixel on the screen to the terrain coordinates that represent that pixel.

It is advised to use IRender4::ScreenToWorld() instead of the this method.

HRESULT ScreenToTerrain(

[in] int X,

[in] int Y,

[out] VARIANT* doubleTerrainX,

[out] VARIANT* doubleTerrainY,

[out] VARIANT* doubleTerrainElevation)

Parameters:

• X – The x-coordinate, in pixels, of the point whose corresponding terrain coordinate you are seeking

• Note: This pixel is relative to the top-left corner of the 3D window whose coordinates are (0, 0).

• Y – The y-coordinate, in pixels (given in render coordinates), of the top-left corner of the 3D Window.

• Note: This pixel is relative to the top-left corner of the 3D window whose coordinates are (0, 0).

• doubleTerrainX – The terrain x-coordinate that corresponds to the given pixel.

• doubleTerrainY – The terrain y-coordinate that corresponds to the given pixel.

• doubleTerrainElevation – The terrain height that corresponds to the given pixel.

Note: The height coordinate is returned here in MPT coordinates and not relative to the ground since, in that case, it would always be zero.

Return Values:

The return value obtained from the returned HRESULT can be one of the following:

Remarks:

If a pixel that is chosen does not fall in the 3D Window, the terrain coordinates that are returned have are all zero.