Second Life Physics Scripting - Pinball #22 - llRezObject ball

I'm beginning to think I can use a different blog entry title and may change to Second Life Game Scripting on the next one since I'm no longer really dealing with physics and have moved onto building the game elements?

The next step is to spawn the ball (llRezObject) when the game starts, and to remove the ball when it hits the back wall. I decided to make the first attempt fairly simple and just rez the ball in the center of the table when the up key is pressed. This seemed pretty straight forward and didn't seem to take very long. Reading up on how to do it took most of the time. Here is the code that I used to rez the ball from inventory.

    control(key id, integer held, integer change)
    {
        ... code for the flipper controls ...
        if ((held&CONTROL_UP) && (change&CONTROL_UP))
        {
            if (!in_play)
            {
                in_play = TRUE;
                
                llSay(0," here we go!!!");
                
                // find the size of the this table
                vector sz = llList2Vector(llGetPrimitiveParams([PRIM_SIZE]),0);
                
                vector pos = llGetPos();
                llOwnerSay("pos = "+(string)pos);
                vector up = llVecNorm(pos * llGetLocalRot());
                up = up * ((sz.z/2) + 0.21); // add the size of the ball
                llOwnerSay("up = "+(string)up);
                
                pos = pos + up;
                llOwnerSay("rez pos = "+(string) pos);
                
                llRezObject("ball",pos,<0,0,0>,ZERO_ROTATION,0);
            }
        }
    }

Adding the ball to inventory was pretty simple. Select the root object and drag the ball from my inventory into the root object's contents. The contents are the same place all the scripts are stored. The first time I did this it took me a while to figure out that you could also store objects in the contents, not just scripts.

Next up I have to change the collision script on the back wall to derez the ball instead of bouncing it back. Then I'll have to send a message to the root prim so I can reset the in_play flag so the person can rez another ball. From there it's a matter of giving each player a set number of balls and keeping track of a high score. Getting closer to a full circle game....