Some basic concepts of motion law in Flash

The activity image in the concept cartoon, unlike other films, film directly with the movement of objects, but through the movement of the objective object observation, analysis, research, with the performance of animation techniques (mainly exaggerated, emphasizing some aspects of the movement over), a piece of painting out, a piece of film, and then the continuous show, Making it active on the screen. 　　Therefore, the motion law of the object should be based on the movement law of the objective object, but it has its own characteristics, not simple simulation. In order to study the motion law of the object, we should first understand the concept of time, space, number, speed and the relationship between each other, so as to master the law and handle the rhythm of the action in animation.

　　Time

The term "time" refers to the length of time required by an object (both biological and non-biological) in a film to complete an action, and the length of the film (the number of pieces). This action takes a long time, it occupies a lot of the number of pieces, the action takes a short time, it occupies a small number of pieces.

Because the action rhythm of the cartoon is relatively quick, the lens is relatively short (a 10-minute animated film is roughly cut into a 100~200 lens), therefore, when calculating the time (length) of a lens or an action, the requirement is more precise, except in seconds (feet), and in the case of "lattice" (1 sec =24 , 1 sq ft = 16 square).

The tool used in the animation calculation time is a stopwatch. After thinking good action, oneself one side does the action, side uses the stopwatch to measure the time, also may one person do the movement, another person measure time. For some of the action can not be made, such as the Monkey King in the air somersault, eagles soar in the sky or snow clouds tumbling, and so on, often with gestures to do some analogy, while using a stopwatch to measure time, or according to their own experience, using the brain Mers to determine the time required for such action For some of the action you are not familiar with, you can take action reference film, the action recorded, and then calculate the action on the film on the length (feet, lattice), determine the time required.

In practice, we found that the film's length is shorter than that of the feature films and documentaries when the same action is done. For example, to use film to shoot a real person to walk at normal speed, if each step is 14 lattice, then the animated cartoon often only takes 12 lattice, can cause the real person each step to walk with 14 feet speed the effect; If the cartoon also uses 14 lattice, on the screen will feel than the real person each step to walk with 14 feet slightly slower. This is because of the animation of a single flat-coated modelling is simpler. Therefore, when we determine the time required for an action in a cartoon, we often have to use a stopwatch based on the time measured by a live show or the length of the record, a slight discount to achieve the desired effect.

　　Space

The so-called "space" can be understood as animated animation in the image of the activity in the range and location, but more important is the amplitude of an action (that is, an action from the beginning to the end of the distance) and the activity of the image of the distance between each picture.

Animation designers in the design of action, often the amplitude of the action to deal with more than the magnitude of the actual action to exaggerate a bit, in order to achieve a more sharp and strong effect.

In addition, the animated animation in the depth of movement, can be compared with the background screen through the perspective of the depth of the distance inconsistent. For example: the performance of a person from the scene in depth from the head, from small to large, if according to the picture perspective and the proportion of the background and characters, should run 10 steps, then in the animated cartoon as long as five or six steps can be, especially in the lower horizon situation, more so.

　　Speed

The so-called "speed" refers to the movement of objects in the process of speed. According to physics, the distance is the ratio of the time spent in the passage. In the same distance, the faster the movement of the object the shorter the time spent, the slower the movement of the object will take longer. In cartoons, the faster the object moves, the less the number of cells it takes, and the slower the object moves, the more the number of cells is taken.

　　Constant speed, acceleration and deceleration

According to the explanation of physics, if the distance that the particle passes is equal in any equal time, then the motion of the particle is uniform velocity, and if the distance of the particle is not equal in any equal time, then the motion of the particle is not uniform. (In the analysis of physics, in order to simplify the problem, a point is usually substituted for an object, which is used to replace the point of an object, called a particle.) ）

　　The relationship between time, distance, number and speed

The basic concepts of time, distance, number, speed, from an action (not a group of actions), the so-called "time", is the original nail painting Dynamic step-by-step movement to the original picture of the number of seconds required (feet, lattice) how much; the so-called "distance" refers to the number of two of the original painting between the amount of the quantity; the so-called "speed", is the original fingernail painting dynamic to the original painting dynamic speed.

Now, we analyze the relationship between time, distance, number three factors and speed. As for this problem, beginners tend to produce an illusion: the longer the time, the farther away, the more the number of sheets, the slower the speed, the shorter the time, the nearer the distance, the faster the number of sheets. But sometimes this is not the case, for example:

Group A: Animation 24, each shot a lattice, a total of 24 cells = 1 seconds, the distance is twice times the Group B.

Group B: Animation 12, each shot a lattice, a total of 12 cells = 0.5 seconds, distance is half of group A.

Although the group A's time and the number of sheets are one times more than the group B, but because the distance of group A is also longer than the second group, if the group a half, you will find that the time, distance and number of the group B is exactly the same, so the speed of the movement is not slow. This shows that when the impact of the speed of the three factors are correspondingly increased or decreased, the speed of movement is unchanged. The speed of motion changes only when one or both of these three factors are treated in the opposite direction, for example:

Group A: Animation 12, each shot a lattice, a total of 12 cells = 0.5 seconds, the distance is twice times the Group B.

Group B: Animation 12, each shot a lattice, a total of 12 cells = 0.5 seconds, distance is half of group A.

The range of Group A is twice times that of Group B, and its speed is correspondingly faster. This shows: In the same time as the number of sheets, the greater the distance, the faster the speed, the smaller the distance, the slower the speed.

It should be explained that, in order to describe the convenience, the above is a uniform motion for example, not only the total distance is equal, and the distance between each animation is also equal. In fact, even if the two sets of animation of the total distance of the same motion, if the distance between each animation is not the same (with the acceleration or deceleration of the method to deal with), will cause different speed and speed of the effect.