cnq3/code/renderer/shaders/crp/vl_debug_ambient.hlsl
myT 30150e889e added sunlight and volumetric lighting
fixed depth linearization
2024-03-29 04:19:38 +01:00

101 lines
3.5 KiB
HLSL

/*
===========================================================================
Copyright (C) 2024 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/>.
===========================================================================
*/
// volumetric lighting: visualize the bsp light grid as a bunch of raytraced spheres
#include "common.hlsli"
#include "scene_view.h.hlsli"
cbuffer RootConstants
{
float3 centerPosition;
float sphereScale;
float3 worldScale;
uint lightGridTextureAIndex;
uint lightGridTextureBIndex;
}
struct VOut
{
float4 position : SV_Position;
float3 positionWS : POSITIONWS;
float4 sphere : SPHERE;
int3 voxelIndex : VOXELINDEX;
};
VOut vs(uint vertexId : SV_VertexID)
{
Texture3D lightGridTexture = ResourceDescriptorHeap[lightGridTextureAIndex];
SceneView scene = GetSceneView();
uint3 textureSize = GetTextureSize(lightGridTexture);
uint flatVoxelIndex = vertexId / 6;
uint vertexIndex = vertexId % 6;
int3 voxelIndex = int3(UnflattenIndex(flatVoxelIndex, textureSize));
float3 voxelCenter = AABoxIndexToWorldSpace(voxelIndex, centerPosition, float3(textureSize), worldScale);
float2 quadPosition = QuadFromVertexID(vertexIndex);
float radius = 0.5 * sphereScale * min3(worldScale.x, worldScale.y, worldScale.z);
float3 up = scene.cameraUp;
float3 forward = normalize(voxelCenter - scene.cameraPosition);
float3 right = normalize(cross(forward, up));
up = cross(right, forward);
float3x3 rotMat = float3x3(right, up, forward);
float distToSphere = length(scene.cameraPosition - voxelCenter);
float sinAngle = radius / distToSphere;
float cosAngle = sqrt(1.0 - sinAngle * sinAngle);
float tanAngle = sinAngle / cosAngle;
float quadScale = tanAngle * distToSphere * 2.0;
float3 positionWS = voxelCenter + quadScale * mul(float3(quadPosition, 0), rotMat);
float4 positionVS = mul(scene.viewMatrix, float4(positionWS, 1));
float4 position = mul(scene.projectionMatrix, positionVS);
VOut output;
output.position = position;
output.positionWS = positionWS;
output.sphere = float4(voxelCenter, radius);
output.voxelIndex = voxelIndex;
return output;
}
float4 ps(VOut input) : SV_Target
{
Texture3D lightGridTextureA = ResourceDescriptorHeap[lightGridTextureAIndex];
Texture3D lightGridTextureB = ResourceDescriptorHeap[lightGridTextureBIndex];
SceneView scene = GetSceneView();
float3 rayDir = normalize(input.positionWS - scene.cameraPosition);
float t = RaytraceSphere(scene.cameraPosition, rayDir, input.sphere.xyz, input.sphere.w);
if(t < 0.0)
{
discard;
}
float4 payloadA = lightGridTextureA[input.voxelIndex];
float4 payloadB = lightGridTextureB[input.voxelIndex];
float3 hitPosition = scene.cameraPosition + rayDir * t;
float3 normal = normalize(hitPosition - input.sphere.xyz);
float3 color = AmbientColor(payloadA, payloadB, normal, scene.ambientColor);
float4 result = float4(color * 0.5, 1);
return result;
}