b2TensorDampingController.cpp
上传用户:gb3593
上传日期:2022-01-07
资源大小:3028k
文件大小:2k
源码类别:
游戏引擎
开发平台:
Visual C++
- /*
- * Copyright (c) 2006-2007 Erin Catto http://www.gphysics.com
- *
- * This software is provided 'as-is', without any express or implied
- * warranty. In no event will the authors be held liable for any damages
- * arising from the use of this software.
- * Permission is granted to anyone to use this software for any purpose,
- * including commercial applications, and to alter it and redistribute it
- * freely, subject to the following restrictions:
- * 1. The origin of this software must not be misrepresented; you must not
- * claim that you wrote the original software. If you use this software
- * in a product, an acknowledgment in the product documentation would be
- * appreciated but is not required.
- * 2. Altered source versions must be plainly marked as such, and must not be
- * misrepresented as being the original software.
- * 3. This notice may not be removed or altered from any source distribution.
- */
- #include "b2TensorDampingController.h"
- b2TensorDampingController::b2TensorDampingController(const b2TensorDampingControllerDef* def) : b2Controller(def)
- {
- T = def->T;
- maxTimestep = def->maxTimestep;
- }
- void b2TensorDampingController::Step(const b2TimeStep& step)
- {
- float32 timestep = step.dt;
- if(timestep<=B2_FLT_EPSILON)
- return;
- if(timestep>maxTimestep && maxTimestep>0)
- timestep = maxTimestep;
- for(b2ControllerEdge *i=m_bodyList;i;i=i->nextBody){
- b2Body* body = i->body;
- if(body->IsSleeping())
- continue;
- b2Vec2 damping = body->GetWorldVector(
- b2Mul(T,
- body->GetLocalVector(
- body->GetLinearVelocity()
- )
- )
- );
- body->SetLinearVelocity(body->GetLinearVelocity() + timestep * damping);
- }
- }
- void b2TensorDampingControllerDef::SetAxisAligned(float32 xDamping, float32 yDamping)
- {
- T.col1.x = -xDamping;
- T.col1.y = 0;
- T.col2.x = 0;
- T.col2.y = -yDamping;
- if(xDamping>0 || yDamping>0){
- maxTimestep = 1/b2Max(xDamping,yDamping);
- }else{
- maxTimestep = 0;
- }
- }
- void b2TensorDampingController::Destroy(b2BlockAllocator* allocator)
- {
- allocator->Free(this, sizeof(b2TensorDampingController));
- }
- b2TensorDampingController* b2TensorDampingControllerDef::Create(b2BlockAllocator* allocator) const
- {
- void* mem = allocator->Allocate(sizeof(b2TensorDampingController));
- return new (mem) b2TensorDampingController(this);
- }