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Camera Up Vector


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I'm trying, using my own shader, to make a billboard  using a predefined XZ plane mesh. 

to do so, i first build the necessary vector (into my own material) to pass to the shader,

                var cam = scene.activeCamera;
                var look = cam.position.subtract(mesh.position).normalize();
                var view = scene.getViewMatrix();
                var up = new BABYLON.Vector3(view.m[1], view.m[5], view.m[9]);
                var right = BABYLON.Vector3.Cross(up, look);

                this._effect.setMatrix(__world_str, world);
                this._effect.setMatrix(__worldViewProjection_str, world.multiply(scene.getTransformMatrix()));
                this._effect.setVector3(__upVector_str, up);
                this._effect.setVector3(__rightVector_str, right);
                this._effect.setVector3(__center_str, mesh.position);

then use the values into the shader as :

	vec3 newp = center + (upVector * position.x) + (rightVector * position.z);
	vec4 outPosition = worldViewProjection * vec4(newp, 1.);
	gl_Position = outPosition;

where center is the center of the billboard.

I use an ArcRotateCamera.

However, this is NOT render properly. The plane is ALWAYS facing the camera, which is good, BUT it strectch vertically when spining arround.. What i have missed ??? 



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Hi Guy, found the solution..

the code is correct, was a scalling not set correctly on Y into the mesh and while the scalling is apply after the tranformation (part of the world matrix), it's strech the mesh on X and Z but NOT on Y. I let the code for thus interested by the billboard shader subject.

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