doom3-bfg/base/renderprogs/simpleshade.pixel
2014-08-02 14:36:46 +02:00

62 lines
No EOL
2.6 KiB
Text

/*
===========================================================================
Doom 3 BFG Edition GPL Source Code
Copyright (C) 1993-2012 id Software LLC, a ZeniMax Media company.
This file is part of the Doom 3 BFG Edition GPL Source Code ("Doom 3 BFG Edition Source Code").
Doom 3 BFG Edition Source Code is free software: you can redistribute it and/or modify
it under the terms of the GNU General Public License as published by
the Free Software Foundation, either version 3 of the License, or
(at your option) any later version.
Doom 3 BFG Edition Source Code is distributed in the hope that it will be useful,
but WITHOUT ANY WARRANTY; without even the implied warranty of
MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE. See the
GNU General Public License for more details.
You should have received a copy of the GNU General Public License
along with Doom 3 BFG Edition Source Code. If not, see <http://www.gnu.org/licenses/>.
In addition, the Doom 3 BFG Edition Source Code is also subject to certain additional terms. You should have received a copy of these additional terms immediately following the terms and conditions of the GNU General Public License which accompanied the Doom 3 BFG Edition Source Code. If not, please request a copy in writing from id Software at the address below.
If you have questions concerning this license or the applicable additional terms, you may contact in writing id Software LLC, c/o ZeniMax Media Inc., Suite 120, Rockville, Maryland 20850 USA.
===========================================================================
*/
#include "renderprogs/global.inc"
struct PS_IN {
float4 position : VPOS;
float4 texcoord0 : TEXCOORD0_centroid;
};
struct PS_OUT {
float4 color : COLOR;
};
uniform sampler2D samp0 : register(s0);
static float2 screenPosToTexcoord( float2 pos, float4 bias_scale ) { return ( pos * bias_scale.zw + bias_scale.xy ); }
void main( PS_IN fragment, out PS_OUT result ) {
const float renderWidth = 1280.0f;
const float renderHeight = 720.0f;
const float4 positionToViewTexture = float4( 0.5f / renderWidth, 0.5f / renderHeight, 1.0f / renderWidth, 1.0f / renderHeight );
float interpolatedZOverW = ( 1.0 - ( fragment.texcoord0.z / fragment.texcoord0.w ) );
float3 pos;
pos.z = 1.0 / interpolatedZOverW;
pos.xy = pos.z * ( 2.0 * screenPosToTexcoord( fragment.position.xy, positionToViewTexture ) - 1.0 );
float3 normal = normalize( cross( ddy( pos ), ddx( pos ) ) );
// light is above and to the right in the eye plane
float3 L = normalize( float3( 1.0, 1.0, 0.0 ) - pos );
result.color.xyz = _float3( dot3( normal, L ) * 0.75 );
result.color.w = 1.0;
}