ok my concern was actually how i am accessing the components, ie. GetActivePrimitive() and GetPolygons() etc. i was afraid those would be slow vs say CGeometryAccessor, although the data is boiled down it may still be useful and faster than directly accessing the component. i could cache the data like the PickBuffer and query
GetGeometry() or GetGeometryAccessor()? s On Mon, Jul 30, 2012 at 1:02 PM, Brent McPherson < [email protected]> wrote: > Steven, > > You are passing siPolygonFilter to the pickbuffer so you can call > GetComponentIndexAtPosition on the pick buffer to get the polygon under the > cursor directly so you don't need to call Snap. > > In other words the pickbuffer has both object *and* polygon information > for each pixel. > > m_pBuffer = in_ctxt.GetPickBuffer(x, y, 1, 1, siPolygonFilter, m_targets, > siShaded); > CRef l_obj = m_pBuffer.GetObjectAtPosition(x, y); > m_hit = l_obj.IsValid(); > if (m_hit) > { > LONG polyIndex = m_pBuffer.GetComponentIndexAtPosition(x, y); > if (polyIndex >= 0) > { > // Get normal for polygon etc.... > Snap is good enough for many tools but it searches through all the > objects/components so you lose the constant time performance of the > pickbuffer. For things like painting where you might be generating a lot of > brush stamps it can make a big difference. > > In your code below the overhead of calling Snap completely eliminates any > benefit gained from the pickbuffer. In fact, you would get the same > performance if you removed the PickBuffer calls and just called Snap. > -- > Brent > > From: [email protected] [mailto: > [email protected]] On Behalf Of Steven Caron > Sent: 30 July 2012 18:45 > To: [email protected] > Subject: Re: SDK : caching the tool context pick buffer > > aah... too bad it was never exposed to the SDK so it could earn its name ;) > > while i have you, how is the GAP/XSI Brush Tool querying normals for brush > orientation? i am doing something like this, excuse the assumption about > getting a single node normal... > > m_pBuffer = in_ctxt.GetPickBuffer(x, y, 1, 1, siPolygonFilter, m_targets, > siShaded); > CRef l_obj = m_pBuffer.GetObjectAtPosition(x, y); > m_hit = l_obj.IsValid(); > if (m_hit) > { > CStringArray families; > families.Add(siMeshFamily); > in_ctxt.Snap(x, y, 1, siSnapFace, families, m_targets, m_pos); > LONG l_compIdx = m_pBuffer.GetComponentIndexAtPosition(x, y); > X3DObject l_xObj(l_obj); > PolygonMesh l_polymesh = l_xObj.GetActivePrimitive().GetGeometry(); > PolygonFace face = l_polymesh.GetPolygons().GetItem(l_compIdx); > PolygonNode node(face.GetNodes().GetItem(0)); > bool validN; > m_normal = node.GetNormal(validN); > m_normal *= > l_xObj.GetKinematics().GetGlobal().GetTransform().GetRotationMatrix3(); > m_normal.NormalizeInPlace(); > } > > and also in the above code is Snap() fast enough to use for my collision > test to place my brush position on? > > steven > > On Mon, Jul 30, 2012 at 10:15 AM, Brent McPherson < > [email protected]<mailto:[email protected]>> wrote: > I though you guys knew all our code names. ;-) > > GAP (Generic Attribute Painter) is what we call the XSI Brush tool. It > uses the pickbuffer to lookup surface info for objects. > -- > Brent > > > From: [email protected]<mailto: > [email protected]> [mailto: > [email protected]<mailto: > [email protected]>] On Behalf Of Steven Caron > Sent: 30 July 2012 17:54 > To: [email protected]<mailto:[email protected] > > > Subject: Re: SDK : caching the tool context pick buffer > > thanks for the reply Brent! > > using a dirty flag is totally fine, i think it was just late and i > couldn't think of such a obvious answer. i dont think an IsValid method is > needed for the PickBuffer, i can use IsNavigating() or use the activate > callback to set the flag. > > i am not at the point where i am thinking about caching multiple views but > thanks for the reminder :) > > i am not familiar with the term 'GAP-like', care to elaborate? > > steven > On Mon, Jul 30, 2012 at 5:13 AM, Brent McPherson < > [email protected]<mailto:[email protected]><mailto: > [email protected]<mailto:[email protected]>>> wrote: > Hi Steven, > > Why don't you keep a dirty flag for the pickbuffer and simply set that in > Activate and then the next time you ask for the pickbuffer (in mouse move > or mouse down) recompute it if it is dirty. > > The pickbuffer is specific to a particular view so you can't generate it > is a callback like Activate which is not tied to any particular view. The > same holds for methods like GetMousePosition. It will return CStatus::Fail > when called from Activate. I guess we should have added an IsValid method > to the pickbuffer but as a workaround you can assume that if GetViewIndex > returns a value greater or equal to zero then it is safe to call > GetPickBuffer. You will also need to decide if you are going to cache a > pickbuffer for each view or just keep one for the last view etc... > > The pickbuffer stuff was designed with this purpose in mind and one of our > consulting devs used it to do a real-time (GAP-like) sculpting tool for a > client. > -- > Brent > From: [email protected]<mailto: > [email protected]><mailto: > [email protected]<mailto: > [email protected]>> [mailto: > [email protected]<mailto: > [email protected]><mailto: > [email protected]<mailto: > [email protected]>>] On Behalf Of Steven Caron > Sent: 30 July 2012 04:43 > To: [email protected]<mailto:[email protected] > ><mailto:[email protected]<mailto: > [email protected]>> > Subject: SDK : caching the tool context pick buffer > > hey guys... (read brent) > > i am trying to cache the PickBuffer each time the user activates this > custom tool (this happens on camera navigation, which is my primary > concern) but not having much luck. the doc suggests if i pass an empty > region i will get the whole view but any subsequent calls i am making to > PickBuffer.GetObjectAtPosition() has returned an invalid reference. is this > doable in the Activate calback? the docs say..."if unavailable in the > current callback or any arguments are invalid then the resulting PickBuffer > will be invalid." > > so, are my arguments incorrect or is this not valid in the this callback? > > // activate callback, called each time the tool comes active again > CStatus Activate(ToolContext& in_ctxt) > { > // get a list of selected meshes > const CString empty; > CStringArray families; > families.Add(siMeshFamily); > Application().GetSelection().GetArray().Filter(empty, families, empty, > m_targets); > > // cache a pick buffer, m_pBuffer is a class member variable where i am > caching it > m_pBuffer = in_ctxt.GetPickBuffer(x, y, width, height, siPolygonFilter, > m_targets, siShaded); > LONG x,y; > in_ctxt.GetMousePosition(x, y); > CRef l_obj = m_pBuffer.GetObjectAtPosition(x, y); > Application().LogMessage(L"Activate : " + l_obj.GetAsText()); > > return CStatus::OK; > }; > > any other tips on caching the PickBuffer each time the camera changes? > > steven > >
