Gl.Ortho (gb.opengl)
Static Sub Ortho ( Left As Float, Right As Float, Bottom As Float, Top As Float, Near As Float, Far As Float )
Multiply the current matrix with an orthographic matrix.
Parameters
- left, right
-
Specify the coordinates for the left and right vertical clipping planes.
- bottom, top
-
Specify the coordinates for the bottom and top horizontal clipping planes.
- nearVal, farVal
-
Specify the distances to the nearer and farther depth clipping planes.
These values are negative if the plane is to be behind the viewer.
Description
Gl.Ortho describes a transformation that produces a parallel projection.
The current matrix (see
Gl.MatrixMode) is multiplied by this matrix
and the result replaces the current matrix, as if
Gl.MultMatrix were called with the following matrix
as its argument:
where
Typically, the matrix mode is Gl.PROJECTION, and
and
specify the points on the near clipping plane that are mapped
to the lower left and upper right corners of the window,
respectively,
assuming that the eye is located at (0, 0, 0).
specifies the location of the far clipping plane.
Both
nearVal and
farVal can be either positive or negative.
Use
Gl.PushMatrix and
Gl.PopMatrix to save and restore
the current matrix stack.
Errors
Gl.INVALID_VALUE is generated if
left =
right, or
bottom =
top, or
near =
far.
Gl.INVALID_OPERATION is generated if
Gl.Ortho
is executed between the execution of
Gl.Begin
and the corresponding execution of Gl.End.
Associated Gets
Gl.Get with argument Gl.MATRIX_MODE
Gl.Get with argument Gl.COLOR_MATRIX
Gl.Get with argument Gl.MODELVIEW_MATRIX
Gl.Get with argument Gl.PROJECTION_MATRIX
Gl.Get with argument Gl.TEXTURE_MATRIX
See also
See original documentation on OpenGL website