cnq3/code/renderer/shaders/grp/dynamic_light.hlsl

128 lines
3.3 KiB
HLSL

/*
===========================================================================
Copyright (C) 2019-2023 Gian 'myT' Schellenbaum
This file is part of Challenge Quake 3 (CNQ3).
Challenge Quake 3 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 2 of the License,
or (at your option) any later version.
Challenge Quake 3 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 Challenge Quake 3. If not, see <https://www.gnu.org/licenses/>.
===========================================================================
*/
// dynamic light shader
#if VERTEX_SHADER
struct VIn
{
float3 position : POSITION;
float3 normal : NORMAL;
float2 texCoords : TEXCOORD0;
float4 color : COLOR0;
};
#endif
struct VOut
{
float4 position : SV_Position;
float3 normal : NORMAL;
float2 texCoords : TEXCOORD0;
float4 color : COLOR0;
float3 osLightVec : TEXCOORD1;
float3 osEyeVec : TEXCOORD2;
};
#if VERTEX_SHADER
cbuffer RootConstants
{
matrix modelViewMatrix;
matrix projectionMatrix;
float4 osLightPos;
float4 osEyePos;
};
VOut vs(VIn input)
{
float4 positionVS = mul(modelViewMatrix, float4(input.position.xyz, 1));
VOut output;
output.position = mul(projectionMatrix, positionVS);
output.normal = input.normal;
output.texCoords = input.texCoords;
output.color = input.color;
output.osLightVec = osLightPos.xyz - input.position.xyz;
output.osEyeVec = osEyePos.xyz - input.position.xyz;
return output;
}
#endif
#if PIXEL_SHADER
#include "shared.hlsli"
cbuffer RootConstants
{
uint4 stageIndices; // low 16 = texture, high 16 = sampler
float3 color;
float recSqrRadius; // 1 / (r * r)
float greyscale;
float intensity;
float opaque;
};
Texture2D textures2D[4096] : register(t0);
SamplerState samplers[96] : register(s0);
float BezierEase(float t)
{
return t * t * (3.0 - 2.0 * t);
}
[earlydepthstencil]
float4 ps(VOut input) : SV_Target
{
// fetch data
uint textureIndex = stageIndices.x & 0xFFFF;
uint samplerIndex = stageIndices.x >> 16;
float lightRecSqrRadius = recSqrRadius;
float3 lightColor = color;
float4 baseColored = input.color * textures2D[textureIndex].Sample(samplers[samplerIndex], input.texCoords);
float4 base = MakeGreyscale(baseColored, greyscale);
float3 nL = normalize(input.osLightVec); // normalized object-space light vector
float3 nV = normalize(input.osEyeVec); // normalized object-space view vector
float3 nN = input.normal; // normalized object-space normal vector
// light intensity
float intensFactor = min(dot(input.osLightVec, input.osLightVec) * lightRecSqrRadius, 1.0);
float3 intens = lightColor * BezierEase(1.0 - sqrt(intensFactor));
// specular reflection term (N.H)
float specFactor = min(abs(dot(nN, normalize(nL + nV))), 1.0);
float spec = pow(specFactor, 16.0) * 0.25;
// Lambertian diffuse reflection term (N.L)
float diffuse = min(abs(dot(nN, nL)), 1.0);
float3 color = (base.rgb * diffuse.rrr + spec.rrr) * intens * intensity;
float alpha = lerp(opaque, 1.0, base.a);
float4 final = float4(color.rgb * alpha, alpha);
return final;
}
#endif