} // end of GetWinRTRatio()
/// <summary>
/// Helper function for touch selection of standard 2d UI elements.
/// </summary>
/// <param name="touchPosition">Position to test against</param>
/// <param name="camera">Current camera.</param>
/// <param name="invWorldMatrix">Inverse of element's world matrix.</param>
/// <param name="width">Width of UI element in world units.</param>
/// <param name="height">Height of UI element in world units.</param>
/// <param name="useRtCoords">Assumes rendering to a rendertarget rather than the backbuffer.</param>
/// <returns>UV coord of mouse hit. Should be in [0, 1][0, 1] range. Outside of this implies a miss.</returns>
public static Vector2 GetHitUV(Vector2 touchPosition, Camera camera, ref Matrix invWorldMatrix, float width, float height, bool useRtCoords)
{
Vector2 adjustedTouchPosition = touchPosition;
if (useRtCoords)
{
adjustedTouchPosition = ScreenWarp.ScreenToRT(adjustedTouchPosition);
}
// Get 3D direction for mouse position.
Vector3 touchDir = camera.ScreenToWorldCoords(adjustedTouchPosition);
// Transform mouse ray into local space.
Vector3 position = Vector3.Transform(camera.ActualFrom, invWorldMatrix);
Vector3 direction = Vector3.TransformNormal(touchDir, invWorldMatrix);
// Project to Z==0 plane, calc hit in local units (origin in center).
float dist = -position.Z / direction.Z;
Vector3 hit = position + direction * dist;
Target = hit - invWorldMatrix.Translation;
Vector2 hitUV = new Vector2(hit.X / width + 0.5f, -hit.Y / height + 0.5f);
return(hitUV);
} // end of GetHitUV
/// <summary>
/// Gets the mouse position but transformed into current rendertarget coordinates.
/// Note: This requires that ScreenWarp.FitRtToScreen() has been called with the
/// correct RT size.
/// </summary>
/// <returns></returns>
public static Vector2 GetMouseInRtCoords()
{
Vector2 mousePosition = new Vector2(MouseInput.Position.X, MouseInput.Position.Y);
mousePosition = ScreenWarp.ScreenToRT(mousePosition);
return(mousePosition);
} // end of GetMouseInRtCoords()
/// <summary>
/// Returns it in world coords of ray through touch pixel.
/// </summary>
/// <param name=param name="touchPosition">Position to test against</param>
/// <param name="camera">UiCamera (orthographic)</param>
/// <param name="invWorldMatrix">Inverse of object's world matrix.</param>
/// <param name="useRtCoords">Adjust hit for rendering to a render target?</param>
/// <returns></returns>
public static Vector2 GetHitOrtho(Vector2 touchPosition, UiCamera camera, ref Matrix invWorldMatrix, bool useRtCoords)
{
Vector2 adjustedTouchPosition = touchPosition;
if (useRtCoords)
{
adjustedTouchPosition = ScreenWarp.ScreenToRT(adjustedTouchPosition);
}
Vector2 hit = Vector2.Zero;
// Convert from pixels to world units.
hit.X = adjustedTouchPosition.X * camera.Width / camera.Resolution.X;
hit.Y = adjustedTouchPosition.Y * camera.Height / camera.Resolution.Y;
// Put origin at center.
hit.X -= camera.Width / 2.0f;
hit.Y -= camera.Height / 2.0f;
// Flip vertical axis.
hit.Y = -hit.Y;
Vector3 actualFrom = camera.ActualFrom;
Vector3 actualAt = camera.ActualAt;
// Apply object and camera translation
hit.X += invWorldMatrix.Translation.X + actualAt.X + camera.Offset.X;
hit.Y += invWorldMatrix.Translation.Y + actualAt.Y + camera.Offset.Y;
// Adjust if camera not going along Z axis.
hit.X *= (float)Math.Cos(Math.Atan(camera.ViewDir.X / camera.ViewDir.Z));
hit.Y *= (float)Math.Cos(Math.Atan(camera.ViewDir.Y / camera.ViewDir.Z));
// Need to adjust if object is not at z==0.
if (invWorldMatrix.Translation.Z != 0)
{
float fraction = invWorldMatrix.Translation.Z / (actualFrom.Z - actualAt.Z);
hit.X -= (actualFrom.X - actualAt.X) * fraction;
hit.Y -= (actualFrom.Y - actualAt.Y) * fraction;
}
return(hit);
} // end of GetHitOrtho()
