openGL object real movement simulation - opengl

Question

I need to simulate the movement of a row(oar). The oar object is loaded into eclipse with the min3D library which works with openGL.
At this moment, I make the oar move in the 3 axis x, y and z, but I'm not able to control this movement and to make the oar move in the desired way.
(Don't take care of the values, aren't real values)
This is the class which loads the oar, places it in the screen and moves it:
public class Obj3DView extends RendererFragment {
private Object3dContainer rowObject3D;
/** Called when the activity is first created. */
#Override
public void initScene() {
scene.lights().add(new Light());
scene.lights().add(new Light());
Light myLight = new Light();
myLight.position.setZ(150);
scene.lights().add(myLight);
IParser myParser = Parser.createParser(Parser.Type.OBJ, getResources(), "com.masermic.rowingsoft:raw/row_obj",true);
myParser.parse();
rowObject3D = myParser.getParsedObject();
rowObject3D.position().x = rowObject3D.position().y = rowObject3D.position().z = 0;
rowObject3D.scale().x = rowObject3D.scale().y = rowObject3D.scale().z = 0.28f;
scene.addChild(rowObject3D);
}
//THIS MAKES THE OAR MOVE
#Override
public void updateScene() {
rowObject3D.rotation().x += 1; //pitch
rowObject3D.rotation().z += 1; //roll
rowObject3D.rotation().y += 0.5; //yaw
}
roation() method definition: X/Y/Z euler rotation of object, using Euler angles. Units should be in degrees, to match OpenGL usage.
So the question is about how could I define the values that make the oar simulate a real movement?

Answer 1

This looks more like a mathematics question.
I'll present some general tips;
On positioning:
The fixed point of the oar is where the oar is held on the boat, so the oar's rotation is relative to that point, not the center of the oar.
And on top of that, the boat is moving, so is the oar's "fixed" point.
The order for positioning should be:
Translate to the boat position.
Translate the oar so it's center is relative to the correct spot of the boat.
Apply the oar rotation.
Draw it.
On animation:
It will be easier to animate if you alter your model so the origin is at the point where the oar is fixed, but it may complicate other animations/calculae if you later pretend to do more complex manipulations on the oar.
Interpolation of Euler rotation is a mess, I suggest quartenions. You can grab the angles from that nice picture and interpolate. (if you need Euler, still, you can convert the end result to Euler)
For simple animations, (say you just want the oar to repeatedly rotate in some pattern), hardly you will find a better method then key-frames, that is, create a list of coordinates/angles along the path you want the oar to do, and iterate through them, interpolating.
With enough points, a simple linear interpolation will do just fine.