Renald's falling snow page 4

Step 12. We need to use the grid as a guide to placing the circles to make the frame animations. Go to File>Preferences>General Program Preferences>Rulers and Units and set the settings as in the illustration above. Choose a line colour that you find easy to see, and which will let you see the green circles comfortably too. Switch the grid on to make it visible. (View>Grid or the grid button if you have it on your toolbar.) Your image will now look like the one on the right which is zoomed to 1:2.
There are 12 squares across the grid, and this is going to give us a 12 frame animation. I admit that this is going to be a big file and a slow loader, but with a 300 pixel canvas and a 250 pixel globe size, this is the only grid size which will let the circles for the snow frames fit exactly inside the grid. It is important for your first globe done like this that the grid should be a perfect guide for you. A grid of 30x30 would give 10 squares across and ten frames and would be more than enough, but you would have to judge the distance between the selection and the grid lines visually.
Once you have done one globe so you know what is happening, you will be able to use a grid which is not a perfect fit as a rough guide, make the adjustments visually, and reduce the number of frames. In practice I would probably use a 40x40 grid, which would give 7-and-a-bit squares across, and 8 frames. But for now we will make this easy and have extra frames. The consolation is that once this big file has loaded, the animation will be very smooth.
Step13. Zoom in on your snow image so that the ratio is 1:1. Scroll down to the bottom of the image so that you can see the whole of the lower green circle. Click on the layer palette and then on the Merged layer name to make that the current layer. (If your layer palette is not visible in the workspace, use View>Toolbars and check Layer Palette in the list.)

Step 14. Click on the selection tool. In the Tool Options make sure that the selection type is circle and antialias is checked. Place the cursor at 150,450 and drag the selection until the size co-ordinates at the bottom of the screen read 250,250. You will be able to select the exact 250,250 size. If your green circle was a pixel out as mine was the 'marching ants' will not fit perfectly round the green circle, but they will be exactly touching grid lines.
Copy the selection to the clipboard. (Use the copy button if you have it on your toolbar, or Edit>Copy).
On the next page we will apply this to the elf image and make our first layer of snow.