MULTIPLE SELECTION

By JerryDean SmithChad AdamsKarl Mullner

Creating Rectangle Class The rectangle needs to be a

ogre.ManualObject-this is done to create the rectangle and gives it special functions that will be used later for the selection of the entities

NOTE: The selection rectangle is always on top of all other objects in the render window

Selection Rectangle Methods

Methods inside of Selection Rectangle Class

def __init__(self,name): def drawBox(self, left, top, right, bottom):

initialization The selection rectangle initialization

method has to setup the Render Queue Group and how the rectangle will be viewed

ogre.ManualObject.__init__(self,name)

self.setRenderQueueGroup(ogre.RenderQueueGroupID.RENDER_QUEUE_OVERLAY)

self.setUseIdentityProjection(True) self.setUseIdentityView(True) self.setQueryFlags(0)

DrawBox The drawBox does a little more than what

it says it has to convert the mouse position to be able to hand the center of screen being 0,0 where normally it would be .5,.5

left = left * 2 - 1 right = right * 2 - 1 top = 1 - top * 2 bottom = 1 - bottom * 2

DrawBox continued.. Then it clears the old rectangle and shows the box. To do this

simply type self.clear()

Begin sets up the material and type of shape drawn self.begin("", ogre.RenderOperation.OT_LINE_STRIP)

It is important to remember that you need five points when drawing a box you must connect the box back to the beginning self.position(left, top, -1) self.position(right, top, -1) self.position(right, bottom, -1) self.position(left, bottom, -1) self.position(left, top, -1) self.end()

DrawBox continued.. In the intermediate tutorial we were told to

put this into the the end of our drawBox ## set the bounding box of the object to

be infinite, so that the camera will ## always be inside of it box = ogre.AxisAlignedBox() box.setInfinite() self.setBoundingBox(box) pass

PlaneQueryListener Class

This is a listener for after the drawBox has completed. This is what puts the selected entities into a list and shows the bounding box of the boats

PlaneQueryListener Methods:

def __init__ ( self): ogre.SceneQueryListener.__init__ ( self ) self.selectObjects = []

def queryResult ( self, firstMovable): firstMovable.getParentSceneNode().showBoundingBox(True) self.selectObjects.append(firstMovable) return True

def deselectObjects(self): for movableObject in self.selectObjects:

movableObject.getParentSceneNode().showBoundingBox(False) self.selectObjects = []

Selection Manager ClassThis class has the most code crammed into

it so be careful when implementing the class

basically you will be adding a method called

boxSelect and modifying the tick method and some variables in the initialization of the class

initialization We added these variables to make our lives a lot

easier self.box = SelectionRectangle("Box")#creates the box self.engine.gfx.sceneManager.getRootSceneNode()

.createChildSceneNode().attachObject(self.box)#this to get the positions of all the points inside of the rectangle self.mVolQuery =

self.engine.gfx.sceneManager.createPlaneBoundedVolumeQuery(ogre.PlaneBoundedVolumeList())

Initialization continued..#don’t have to do this but we wanted to attach the mouse to self so that we could access the mouse coordinates anywhere self.left = 0.0 self.right = 0.0 self.top = 0.0 self.bottom = 0.0#toggle for the mouse selection self.mouseDown = None#gives access to the listener self.querylistener = PlaneQueryListener()

boxSelecttopLeft = self.engine.gfx.camera.getCameraToViewportRay(self.left, self.top)

do this for all the topRight, bottomLeft and bottomRight

# this is to get the volume of the planesvol = ogre.PlaneBoundedVolume()

boxSelect continued.. Do this function for all five points it will

be projected into the water plane to the boat selection

p = ogre.Plane( topLeft.getPoint(3), topRight.getPoint(3), bottomRight.getPoint(3))

boxSelect continued.. vol.planes.append(p) ## front plane vol.planes.append(p2) ## left plane vol.planes.append(p3) ## bottom plane vol.planes.append(p4) ## top plane vol.planes.append(p5) ## right plane

volList = ogre.PlaneBoundedVolumeList() volList.append(vol)

self.mVolQuery.setVolumes(volList) self.mVolQuery.execute(self.querylistener) resultObjects = self.querylistener.selectObjects

boxSelect continued.. if resultObjects: for name, ent in

self.state.entities.iteritems(): for queryResult in

resultObjects: if queryResult.name ==

ent.gfxNode.name:

self.state.selectedEntities.append(ent) print "Appended"

Selection manager if currMouse.buttonDown(OIS.MB_Left) and not

self.mouseDown: self.bb(isOn = False) self.state.selectedEntities = [] self.left =

float(currMouse.X.abs)/currMouse.width self.top =

float(currMouse.Y.abs)/currMouse.height self.right =

float(currMouse.X.abs)/currMouse.width self.bottom =

float(currMouse.Y.abs)/currMouse.height

Selection manager contiued

if currMouse.buttonDown(OIS.MB_Left) and self.mouseDown:

self.right = float(currMouse.X.abs)/currMouse.width

self.bottom = float(currMouse.Y.abs)/currMouse.height

self.box.drawBox(self.left,self.top,self.right,self.bottom)

self.box.setVisible(True) print self.left,self.right,self.top,self.bottom print "box drawn"

Selection manager contiued

if self.mouseDown and not currMouse.buttonDown(OIS.MB_Left):

if (self.left > self.right): self.left, self.right = self.right, self.left

if (self.top > self.bottom): self.top, self.bottom = self.bottom, self.top self.box.setVisible(False) if ((self.right - self.left) * (self.bottom - self.top) <

0.0001): self.castRay(currMouse) else: self.boxSelect()

Selection manager contiued

if ((currMouse.buttonDown(OIS.MB_Right)) and

(self.toggleSpawn) and not (self.mouseRdown)):

self.spawnRay(currMouse) self.mouseDown =

currMouse.buttonDown(OIS.MB_Left) self.mouseRdown =

currMouse.buttonDown(OIS.MB_Right)