What I'm wanting to do it pass in window client area screen coordinates and have them transformed into projection space to be mapped to the screen within my d3d window using
X [-1,1]
y [-1,1]
float2 screenToPostProjection(float2 screen, float2 ViewPort)
{
float2 normalizedScreen = float2( screen.x / ViewPort.x, screen.y / ViewPort.y);
float2 postProjection = normalizedScreen * 2.0 - 1.0; // mapping from [0,1] to [-1,1]
postProjection.y *= -1; // window origin is in different corner.
return postProjection;
}
My Screen Coordinates Im Passing in are the following:
top left vertex: ( 100, 300 )
top right vertex: ( 700, 300 )
bottom right vertex: ( 700, 800 )
bottom left vertex: ( 100, 800 )
Performing the above transformation on each vertex yields the following results:
top left vertex: ( -.6875, -.25 )
top right vertex: ( 1.1875, -.25 )
bottom right vertex: ( 1.1875, -2.333 )
bottom left vertex: ( -.6875, -2.3333 )
something is not right
some of the values above are outside of the [-1 - 1] range that they must be provided within
