Today we’ll talk about some basic knowledge about the path starting from a fantastic entry point, the Penrose triangle. You may also try to draw the Penrose heptagon if you’re interested.
What is optical illusion?
An optical illusion, also called a visual illusion, achieves an artistic or magic effect by making visually perceived images through measures such as geometric arrangement, vision imaging etc. to deceive people’s eyes and cause vision illusion.
Though he is a Sir as well as a professor at the University of Oxford, Penrose is not rigid at all. Optimistic and outgoing, he is enthusiastic about recreational mathematics, for example, the Penrose triangle. It appears to be a solid object, made of three cuboids whose cross sections are squares, the three cuboids combine to be a triangle, but the included angles between each two cuboids all seem to be right angles.
Now, let’s get straight to the point, we’ll begin to draw the Penrose triangle.
Step 2. Press Ctrl+T to transform the layer, and then cut the horizontal bevel to be -30 degrees.
Press Ctrl+J to copy this layer, press Ctrl+T to transform the layer, flip horizontally and rotate -60 degrees.
3. Press A, select two patterns with the path selection tool box, then press V, use the Move Tool, click the two icons on the top toolbar to make the two layers in top and right alignment, press Ctrl+E to combine them in the end.
5. Copy a layer which was combined just now, rotate it by 120 degrees and align it like just now, but why will there be two extra sections?
To make it clear, I changed the colors of the two complex patterns to be red and cyan. There’s an extra section at the bottom of the red pattern, as a result, the cyan pattern copied from the red one blocks the red pattern. How to solve the problem?
7. All right, in this step, we should have got what we need, so the cyan layer is useless now, it could be deleted.
Now, let’s press A again to select the rectangle we cut just now, change its shape attribute to be “remove the top shape”, in this way, the section at the bottom will be cut off.
8. It is cut off, but it’s over cut on the top and less cut at the bottom.
This is because the three patterns are sorted in a wrong way, you just need to press A to select the horizontal strip, then cut and paste it.
Then how to remove the part at the bottom which is supposed to be cut off? Let’s change a tool first, press Shift+A to swift to the Direct Selection Tool, select the anchor at the bottom, drag it to the left a little bit and the projecting angle will be cut off.
9. Then press CTRL+J to copy this layer, press the number key 5 and the transparency will be 50%, press Ctrl+T to rotate it by 120 degrees, then press Ctrl+Alt+Shift+T to repeat the Ctrl+T operation. Isn’t it very easy? Press 3 to change the transparency of the last layer copied to be 30% and align all the layers, and you will get the Penrose triangle.
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