Need help setting up frustum planes in world/local coordinate space

Help & Support
1

Does camera.frustum.planes array contain the frustum planes in world coordinate space? Or must I do something more? I tried it but doesn’t seem to work but I suspect it’s because the frustum planes are calculated in local coordinate space of the camera by default? Or not? Not too sure…

I need a basis of using camera.frustum.planes (if possible), to try and do standard frustum culling in world/local coordinate spaces.

I don’t get it… It seems the plane’s x,y,z property for the frustum is matching global space, but the offset seems to be tied in the reverse direction? I’m guessing here…

TerrainManage.prototype.calculateFrustum = function() {
	var fru = this.frustum;
	var planes = this.activeCamera.camera.frustum.planes;
	var len = planes.length;
	var i;
	var p;
	var camPos = this.activeCamera.getPosition();
	for(i=0; i<len; i++) {
		p = planes[i];
		fru.x = p[0];
		fru.y = p[1];
		fru.z = p[2];
		fru.offset = fru.x*camPos.x + fru.y*camPos.y + fru.z*camPos.z; //p[3];
		fru = fru.next;
	}
	
	 console.log(planes);
	
	 this.entity.terrainLOD.frustum = this.frustum;
};
2

[SOLVED]

Oh yes, i forgot, The offset for far clip plane[4] vs near-clip plane[5] should be adjusted NOT based off dot product of camera’s position to camera plane, but based off teh camera’s position + nearClip forward vector and camera’s position + farClip forward vector respectively. Doh! Common sense …bleh.

Could the devs explain what p[3] consist off?

Anyway, the fixed code is as follows:

TerrainManage.prototype.calculateFrustum = function() {
	var fru = this.frustum;
	var planes = this.activeCamera.camera.frustum.planes;
 
	var i;
	var p;
	var camPos = this.activeCamera.getPosition();
	var camForward = this.activeCamera.forward;
	var farClip = this.activeCamera.camera.farClip;
	var nearClip = this.activeCamera.camera.nearClip;
	
	 p = planes[5];   // near clip
	 fru.x = p[0];
	fru.y = p[1];
	fru.z = p[2];
	fru.offset = fru.x * (camPos.x +camForward.x*nearClip) + fru.y * (camPos.y +camForward.y*nearClip) + fru.z * (camPos.z +camForward.z*nearClip);
	 fru = fru.next;
	
	p = planes[4];  // far clip
	 fru.x = p[0];
	fru.y = p[1];
	fru.z = p[2];
	fru.offset = fru.x * (camPos.x +camForward.x*farClip) + fru.y * (camPos.y +camForward.y*farClip) + fru.z * (camPos.z +camForward.z*farClip);
	fru = fru.next;
	
	for(i=0; i<4; i++) {
		p = planes[i];
		fru.x = p[0];
		fru.y = p[1];
		fru.z = p[2];
		fru.offset = fru.x*camPos.x + fru.y*camPos.y + fru.z*camPos.z; //p[3];
		fru = fru.next;
	}
	
	// console.log(planes);
	
	 this.entity.terrainLOD.frustum = this.frustum;
};
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