screenspace.cpp

Detailed Description

 1
 2//-----------------------------------------------------------------------------
 3// Copyright (c) 2012 GarageGames, LLC
 4//
 5// Permission is hereby granted, free of charge, to any person obtaining a copy
 6// of this software and associated documentation files (the "Software"), to
 7// deal in the Software without restriction, including without limitation the
 8// rights to use, copy, modify, merge, publish, distribute, sublicense, and/or
 9// sell copies of the Software, and to permit persons to whom the Software is
10// furnished to do so, subject to the following conditions:
11//
12// The above copyright notice and this permission notice shall be included in
13// all copies or substantial portions of the Software.
14//
15// THE SOFTWARE IS PROVIDED "AS IS", WITHOUT WARRANTY OF ANY KIND, EXPRESS OR
16// IMPLIED, INCLUDING BUT NOT LIMITED TO THE WARRANTIES OF MERCHANTABILITY,
17// FITNESS FOR A PARTICULAR PURPOSE AND NONINFRINGEMENT. IN NO EVENT SHALL THE
18// AUTHORS OR COPYRIGHT HOLDERS BE LIABLE FOR ANY CLAIM, DAMAGES OR OTHER
19// LIABILITY, WHETHER IN AN ACTION OF CONTRACT, TORT OR OTHERWISE, ARISING
20// FROM, OUT OF OR IN CONNECTION WITH THE SOFTWARE OR THE USE OR OTHER DEALINGS
21// IN THE SOFTWARE.
22//-----------------------------------------------------------------------------
23
24#include "gfx/util/screenspace.h"
25#include "gfx/gfxDevice.h"
26
27// The conversion from screen space to the render target
28// is made more complex because screen space is relative
29// to the viewport.
30void ScreenSpace::RenderTargetParameters(const Point3I &targetSize, const RectI &targetViewport, Point4F &rtParams)
31{
32   // Top->Down
33   Point2F targetOffset(   (F32)targetViewport.point.x / (F32)targetSize.x,
34                           (F32)targetViewport.point.y / (F32)targetSize.y );
35
36   // Bottom->Up
37   //Point2F targetOffset(   (F32)targetViewport.point.x / (F32)targetSize.x,
38   //                        ( (F32)targetSize.y - (F32)(targetViewport.point.y + targetViewport.extent.y ) ) / (F32)targetSize.y );
39
40
41   // Get the scale to convert from the 
42   // screen space to the target size.
43   Point2F targetScale( (F32)targetViewport.extent.x / (F32)targetSize.x,
44                        (F32)targetViewport.extent.y / (F32)targetSize.y );
45
46
47   rtParams.set( targetOffset.x, targetOffset.y, targetScale.x, targetScale.y );
48}
49