Blender path animation
Path animation is when a vector guides the movement of an object. The user can specify a number a type of movement and then constrain objects to that movement type. In complex animations this ability has a number of benefits.
- The user can easily change the duration of an animation by changing the duration of the path.
- Multiple objects can be attached to one vector. A school of fish or falling leaves require the ability to direct the movement of multiple objects in this way.
- Elegance of this method as opposed to key framing increases the ability to examine an animation and discern what the different components are doing.
Below are instructions on relatively simple path animation.
- I) There is a box at the center of the screen. Right click on the box and press x to erase all. The cursor is the red and white reticule in the center of the screen. Objects you create will appear on the cursor. You can move the cursor by left clicking. Do not move it yet.
- II) We are now going to add the sun. Press spacebar to get a list of possible objects. Go to add-> mesh-> UV sphere. Repeat the previous step. The two spheres now sit on top of each other. Right click on one of them. Then press s to resize it. You now have the components you will use to create a sun.
- III) Now we are going to add a path for a planet. Without moving the cursor press spacebar-> add-> curve-> Bezier Circle. Then press S to resize. Move it so that it is a few boxes out from the sun. Now right click on it.
- a) Here we are going to set the orbit as continuous and the speed of the orbit. Right now the path length (the time it takes for an object to traverse the perimeter of the circle) is 100 keys at 25 keys per second. Hence the orbital time of a planet on that path is 4 seconds. Lets change that to 15 seconds. Hence we want a path length of 375. Press f9 to get the editing panel. Under curve and surface is a option for path length. Delete the number 100 and then enter 375. Now an object linked to this path will go once around the sun over 375 frames. However we still need to make it a continuous orbit.
- b) Press f6 to get to the IPO editor. The ipo editor is an animation editor that regulates the speed of objects and paths over time. The x axis is time the y access is speed. In the IPO window go to the drop down menu that says object and choose path. Press up arrow and then down arrow you should see a green line moving. Press down until it stops. This is coordinate 0,0. Now press control and left-click on point 0,0. There are two black lines to the right of point 0,0 that represent a complete rotation
- c) Now press tab to go into edit mode. Move along the x axis by holding down the scroll wheel. Find 375 then zoom in on coordinate 375,1 by rolling the scroll wheel. Now put the mouse over 375,1 control left click to create a new ipo point. Align the yellow line to the black line in the same way as step 4b. Zoom back out using the scroll wheel and press tab your IPO curve should look like this
- d) Now we have to make movement continuous and smooth. On the IPO menu click curve -> Interpolation mode-> Linear. This straightens the IPO curve. Then press curve-> extend mode-> cyclic. This makes the orbit continuous. Your IPO window now looks like this.
- a) Now we will add a planet and link it to its orbital path. Without moving the cursor add a sphere as per step 2. Then press g for grab and y for constrain and drag it straight down to the perimeter. Zoom in using he scroll wheel and make sure the center dot of the sphere is on top of the orbital path.
- b) Now right-click on the planet hold shift and right click on the path. Then press control p. A drop down menu will appear select follow path. If you press the arrow buttons the planet will now move. Repeat steps 3-5 for as many planet as you want.
- a Now add a camera. Orientate the viewer to a front view by pressing 1. Press spacebar then add->camera. Now orientate the viewer to a top view by pressing 7. Now grab the camera and constrain it to the y axis press g y and drag the camera 6-10 boxes away from the orbit of the outermost planet. Press 0 to make sure that the camera is facing the sun.
- b Now add a straight path for the camera. Press spacebar add->curve->path. Tab into edit mode. You will see that the line has a set of arrows along it. These indicate its direction. Select the whole path by holding shift and clicking on each vertex. Then press r+z to rotate on the z axis. Rotate until the arrows point in the correct direction. Now press s to resize the path. Make the path large enough to pass through all of the orbits of the planets.
- c Now grab the camera and constrain it to the y axis g+y. Drag the camera until it is at the beginning of the path. Align the dot on the rear of the camera and the dot at the beginning of the path. Now select the camera right-click and select the path shift + right-click. Now Press control+p->follow path. The camera will now move along this path through the scene. Follow steps 4b and 4c to make an IPO curve for the camera that will dictate the speed of the camera's movement. Press 0 tp go into camera mode then alt+a to go watch the animation. Add lighting and then render.