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POHow do people render so many voxels at once?
 

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  1. POHow do people render so many voxels at once?
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    <p>I have actually 2 questions. 1) I see these renders of thousands of voxels, yet using an octree I can still get only about 500 voxels on the screen.</p> <pre><code>import warnings,sys sys.setrecursionlimit(50000) class storedItem(): def __init__(self,coord,data): self.coord = coord self.data = data self.node = None def remove(self): self.node.children.remove(self) self.node = None class Node(): def __init__(self,parent,lower,upper): self.parent = parent self.children = [] self.lowerbound = lower self.upperbound = upper self.setVolume() def setVolume(self): dx = self.upperbound[0] - self.lowerbound[0] dy = self.upperbound[1] - self.lowerbound[1] dz = self.upperbound[2] - self.lowerbound[2] self.volume = dx*dy*dz def inbound(self,coord): if self.lowerbound[0] &lt;= coord[0] and self.lowerbound[1] &lt;= coord[1] and self.lowerbound[2] &lt;= coord[2]: if self.upperbound[0] &gt;= coord[0] and self.upperbound[1] &gt;= coord[1] and self.upperbound[2] &gt;= coord[2]: return True return False def returnValueOrChildnode(self,coord): if not self.inbound(coord): return self.parent for child in self.children: if child.__class__ == Node: if child.inbound(coord): return child elif child.__class__ == storedItem: if child.coord == coord: return child return None def deleteOrReturnChildNode(self,coord): if not self.inbound(coord): return self.parent for child in self.children: if child.__class__ == Node: if child.inbound(coord): return child elif child.__class__ == storedItem: if child.coord == coord: self.children.remove(child) del(child) return True return None def insertStoredItem(self,item): if len(self.children) &lt; 8: self.children.append(item) item.node = self return True if len(self.children) == 8: for child in self.children: if child.__class__ == Node: if child.inbound(item.coord): return child.insertStoredItem(item) elif item.coord == child.coord: warnings.warn('Already an item at this location, replacing it') self.children.remove(child) self.children.append(item) self.breakupIntoChildren() self.insertStoredItem(item) def breakupIntoChildren(self): #if self.volume == 8: # raise Exception("Node full. Cannot add to this node") nodes = [] delta = (self.upperbound[0] - self.lowerbound[0] +1)/2 x1,x2,x3 = (self.lowerbound[0],self.lowerbound[0]+delta -1,self.upperbound[0]) y1,y2,y3 = (self.lowerbound[1],self.lowerbound[1]+delta -1,self.upperbound[1]) z1,z2,z3 = (self.lowerbound[2],self.lowerbound[2]+delta -1,self.upperbound[2]) nodes.append(Node(self,(x1,y1,z1),(x2,y2,z2))) nodes.append(Node(self,(x2 + 1,y1,z1),(x3,y2,z2))) nodes.append(Node(self,(x1,y1,z2 +1),(x2,y2,z3))) nodes.append(Node(self,(x2 + 1,y1,z2 + 1),(x3,y2,z3))) nodes.append(Node(self,(x1,y2 + 1,z1),(x2,y3,z2))) nodes.append(Node(self,(x2 + 1,y2 + 1,z1),(x3,y3,z2))) nodes.append(Node(self,(x1,y2 + 1,z2 + 1),(x2,y3,z3))) nodes.append(Node(self,(x2 + 1,y2 + 1,z2 + 1),(x3,y3,z3))) while self.children: child = self.children[0] for node in nodes: if node.inbound(child.coord): node.insertStoredItem(child) self.children.remove(child) self.children = nodes class Octree(): def __init__(self,size,maxsearch=1000): if size % 2: raise Exception("Size must be multiple of 2") self.root = Node(None, (0,0,0),(size,size,size)) self.size = size self.maxsearch=maxsearch def search(self,coord): searching = True node = self.root count = 0 while searching: result = node.returnValueOrChildnode(coord) if result is None: searching = False elif result.__class__ == storedItem: result = result.data searching = False elif result.__class__ == Node: node = result count += 1 if count &gt; self.maxsearch: #just incase something goes wrong searching=False result = None raise Exception("Max Search depth limit reached") return result def insert(self,coord,data): if not self.root.inbound(coord): print coord, self.size, self.root.upperbound, self.root.lowerbound raise Exception("Coordinate outside scope of octree") item = storedItem(coord,data) self.root.insertStoredItem(item) def remove(self,coord): searching = True node = self.root count = 0 while searching: result = node.deleteOrReturnChildNode(coord) if result is True: searching = False return True elif result is None: searching = False elif result.__class__ == Node: node = result count += 1 if count &gt; self.maxsearch: #just incase something goes wrong searching=False result = None raise Exception("Max Search depth limit reached") return result def trace(frame, event, arg): print "%s, %s:%d" % (event, frame.f_code.co_filename, frame.f_lineno) return trace </code></pre> <p>Thats the octree code I've been using. I got it off a website, which was pretty neat. It works great for removing the cubes on the inside. Though it makes it just a hollow box, which is pretty weird. Though it does drastically improve the FPS. For rendering cubes I use this little class.</p> <pre><code>class Cube(object): def __init__(self, position, color,tree): self.position = position self.x = position[0] self.y = position[1] self.z = position[2] self.color = color self.tree = tree num_faces = 6 vertices = [ (0.0, 0.0, 1.0), (1.0, 0.0, 1.0), (1.0, 1.0, 1.0), (0.0, 1.0, 1.0), (0.0, 0.0, 0.0), (1.0, 0.0, 0.0), (1.0, 1.0, 0.0), (0.0, 1.0, 0.0) ] normals = [ (0.0, 0.0, +1.0), # front (0.0, 0.0, -1.0), # back (+1.0, 0.0, 0.0), # right (-1.0, 0.0, 0.0), # left (0.0, +1.0, 0.0), # top (0.0, -1.0, 0.0) ] # bottom vertex_indices = [ (0, 1, 2, 3), # front (4, 5, 6, 7), # back (1, 5, 6, 2), # right (0, 4, 7, 3), # left (3, 2, 6, 7), # top (0, 1, 5, 4) ] # bottom def render(self): glColor( self.color ) # Adjust all the vertices so that the cube is at self.position vertices = [tuple(Vector3(v) + self.position) for v in self.vertices] # Draw all 6 faces of the cube glBegin(GL_QUADS) for face_no in xrange(self.num_faces): glNormal3dv( self.normals[face_no] ) v1, v2, v3, v4 = self.vertex_indices[face_no] glVertex( vertices[v1] ) glVertex( vertices[v2] ) glVertex( vertices[v3] ) glVertex( vertices[v4] ) glEnd() def getneighbors(self): x = self.x y = self.y z = self.z return ((x,y,z+1),(x+1,y,z),(x,y+1,z),(x-1,y,z),(x,y-1,z),(x,y,z-1)) def checkneighbors(self): if not self.tree: return True positions = self.getneighbors() for pos in positions: result = self.tree.search(pos) if not result: return True return False </code></pre> <p>I can get about 30FPS with this code. I think there is about 62,210 squares on the screen. I get usually around 30-40 FPS (which isn't bad.)</p>
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    1. PTQuestion
    1. USBrian Smith
    1. USBrian Smith
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      1. LTLinked
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    1. COWhen you have two independent questions you should ask them independently. I think you can remove your second question as there are enough resources on this (e.g. http://stackoverflow.com/questions/4753055/perlin-noise-generation-for-terrain). To answer your first question you should give more details. How do you render them now?
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      1. POHow do people render so many voxels at once?
      1. USNobody
    2. COPlease show your code. It is impossible to tell why code doesn't work like you expect if you don't show it.
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      1. POHow do people render so many voxels at once?
      1. USRoland Smith
    3. COI added the code.
      singulars
      1. POHow do people render so many voxels at once?
      1. USBrian Smith
 

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