Files
LNXSDK/lib/haxejolt/JoltPhysics/Jolt/Shaders/HairUpdateVelocity.hlsl
2026-03-04 00:50:15 -08:00

41 lines
1.4 KiB
HLSL

// Jolt Physics Library (https://github.com/jrouwe/JoltPhysics)
// SPDX-FileCopyrightText: 2026 Jorrit Rouwe
// SPDX-License-Identifier: MIT
#include "HairUpdateVelocityBindings.h"
#include "HairCommon.h"
#include "HairUpdateVelocity.h"
JPH_SHADER_FUNCTION_BEGIN(void, main, cHairPerVertexBatch, 1, 1)
JPH_SHADER_PARAM_THREAD_ID(tid)
JPH_SHADER_FUNCTION_END
{
// Check if this is a valid vertex
uint vtx = tid.x + cNumStrands; // Skip the root of each strand, it's fixed
if (vtx >= cNumVertices)
return;
if (IsVertexFixed(gVerticesFixed, vtx))
return;
// Load the material
uint strand_idx = vtx % cNumStrands;
JPH_HairMaterial material = gMaterials[GetStrandMaterialIndex(gStrandMaterialIndex, strand_idx)];
// Load the vertex
float strand_fraction = GetVertexStrandFraction(gStrandFractions, vtx);
float3 initial_pos = gInitialPositions[vtx];
float4 initial_bishop = JPH_QuatDecompress(gInitialBishops[vtx]);
JPH_HairGlobalPoseTransform global_pose_transform = gGlobalPoseTransforms[strand_idx];
JPH_HairPosition pos = gPositions[vtx];
JPH_HairPosition prev_pos = gPreviousPositions[vtx];
JPH_HairVelocity vel;
ApplyGlobalPose(pos, initial_pos, initial_bishop, global_pose_transform, material, strand_fraction);
ApplyCollisionAndUpdateVelocity(vtx, pos, prev_pos, material, strand_fraction, vel);
LimitVelocity(vel, material);
// Write back vertex
gPositions[vtx] = pos;
gVelocities[vtx] = vel;
}