[flow_default] Transcription: 02-07-Animation-curves.json

transcriptions/02-07-Animation-curves.json

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+{
+  "audio_file": "02-07-Animation-curves.wav",
+  "text": "Animation curves is one of the beginner's nightmare. But I want them to become your best friends. To display the animation curve of our ball, let's go into the graph editor. Right now, our curves look a bit boxy, not really curved. And this is because we are still in constant interpolation. But it will help us reading them. The curves are just a graphical representation of a value over time. The yellow controller point are currently the different keyframe we have inserted before. If I select the yellow point on the blue curve at frame 7, it has a value of 4 such as the Z location of our bowl. And if I now display all the objects transform channel in the graph editor, we can see that the Z location is highlighted. So the control point I've selected in the graph editor is the key frame value of the Z location of our book. If I double click on one of these channels, it will select all the control points of the current curve. You can hide an unhide curve as you would do with any object in the 3D view. If I press Shift H, I will hide everything but the selected curve. Or you can click on the little I icon to choose whether you want to see or not a curve. With G, I can move the curve. I can press G and Y to constraint the movement on the Y axis or GX to constraint on the X axis. Before we start reading those curves, let's get rid of any of the curves we don't need. Since our ball is not rotating, we can get rid of all the Euler rotation curves by pressing X and we can also get rid of the X and Y locations since our ball is just moving up and down. This is a good practice to get rid of any unwanted channel to keep your graph editor clean. We can find the Z location corresponding value onto the control point of the curve but also in the transform channel of the object. Pressing the N key will open the F-Hurve panel. This is a little n-year to check the position, value and interpolation mode of the keyframe channel. Let's now select all the keyframes, press T and switch to Bezier Interpolation. If we now play the animation we get a way smoother motion of the ball. When you switch from step mode to base mode or curve mode, we call this the Splining Stage. If we have a quick look to our curve now, we can see that the Z location curve is getting a higher value when the ball is getting higher. I will unhide the scale channel by clicking the high icon. I will select the first controller point of those curve and press the dot key on the numpad to zoom on it. You can easily identify the z scale channel which is in blue and allow us to control the height of the bow and the x and y that are one on top of the other that allow us to control the width of the bow. Let's check a couple of examples to better understand the behavior of the curves. In this example, the curve is controlling the rotation of the arrow from a value of minus 90° to plus 90°. The curve is raising rapidly before easing into the frame number 24. And when we scrub through the animation, we can see that we have a big spacing in the beginning of the animation and it gets lower in the end. Using the motion path, we will have a preview on the spacing of this animation. And now we can obviously see the difference of spacing during the animation. And the more vertical the curve is, the larger the spacing. The more horizontal it gets, the smaller the spacing is. In other words, the more vertical the curve, the faster the animation, the more horizontal, the slower. In the next example, let's consider the X location curve of the ball, paying the time. It goes forward in a linear fashion. Now if I activate the Z location curve and I frame it properly, look at all the Z location curve and the motion path we found in the 3D viewport align or are comparable. Again, when the curve is vertical, the sphere rides rapidly. And as the curve gets more horizontal, the sphere rides slower. So if I now give an S shape to my curve, the ball will move slowly in the beginning, then in the middle of the animation, it will accelerate as the curve gets more vertical and in the end it will slow down. We are creating a nising out from the frame zero into a nising in the frame 24. And since we still have the linear motion of the sphere on its x-axis, we can see that the z-curve really looks like the motion path of the sphere. Since my sphere is moving on the x location in a linear fashion, any modification I will add to the Z curve will show in the 3D view as in the graph editor by updating the motion path. You can use the few examples available in the file to play with the curve, recalculate the motion path and check out the spacing. Back to the rotation example, I've modeled the curve so that I have a fast acceleration in the beginning, then a plateau and then an is out and is in and it absolutely reflects on the motion path. The pretty vertical shape of the curve on the first two frame generate a big spacing. The plateau shape or flat shape of the curve indicates that the value is not changing over time, so the arrow will stop, while the final S shape of the curve show an acceleration, then a deceleration into the final frame. To summarize, we have seen that a curve is just the representation of the evolution of a value over time. The more vertical the curve shape, the faster the value change, and it translates in bigger spacing. The more horizontal the curve, the slower the change. Motion wise, it translates in smaller spacing. A flat curve indicates that there is absolutely no change in the value and so no motion.",
+  "language": "en",
+  "confidence": null,
+  "duration": 405.23
+}