Step 1: Three-dimensional observation. In this step, we observe and analyze the physical structure and spatial relationship of the objective image, and on this basis, observe the surface factors such as texture, texture and inherent color of the object. When observing the internal structure of the body, we should grasp the object through active observation and tactile experience from multiple viewpoints and angles. Many experienced painters may also be used to observing from a fixed angle, and even less think of touching objects that have been painted many times. Vision distinguishes the structural changes of objects by light and shade, so it is easy to ignore the structural relationship implied by subtle light and shade changes. Tactile experience can make up for the deficiency of vision in this respect and help us understand objects as a whole. Any form has the stipulation of internal structure, no matter how complicated, its structure is derivable, analyzable and representable. The objective form exists in space and is presented in three-dimensional state. In the case of focus perspective, it is difficult to obtain the complex structure of other levels from one angle. In order to deeply understand and study the organizational structure of various parts of the objective form, form a perceptual impression and a stable visual feeling of the form in the brain, and explore the inherent essential characteristics and potential spiritual factors of the object, it is necessary to analyze and analyze the form repeatedly from multiple angles, all directions and at multiple levels.
Usually, although we observe objects from many angles, it is not enough for some objects to observe only from the outside. In plants, the internal structure of many objects is often more characteristic and essential than the external form. Such as tomatoes, pomegranates, oranges, apples and so on. They are all round and look very close, but the difference of internal structure after cutting is great, so only by cutting can we understand the internal structure of the shape and describe the external shape of the object more accurately and clearly.
Through this step of learning, we should change the observation habit of passively accepting visual information and explore the object wholeheartedly. The more comprehensive we observe in front of the object, the more we find and the sharper our observation will be.
Step 2: Two-dimensional observation. After all-round three-dimensional observation of the object image, we choose several fixed viewpoints to observe the axial direction and dynamic situation of the object from a two-dimensional perspective. First, observe the long axis, main direction and main potential of the shape, and then observe the short axis, local direction and secondary potential of the shape. This is an effective process to simplify and master complex tables.
For geometric combinations or symmetrical bodies, the two-dimensional information recorded in plan, elevation and section can help us understand, remember and completely restore the three-dimensional body structure. So drawing three views is an important link in the observation stage.
At this stage, our observation angle should be constantly switched between two-dimensional and three-dimensional ways to achieve the correspondence and coordination between them.
Step 3: Composition. At this stage, we should shift our attention to two-dimensional images, that is, from three-dimensional body structure analysis to two-dimensional plane structure analysis. The first is the choice of horizontal or vertical composition. Pay attention to the length-width ratio of drawing paper and make clear the space limitation of the picture. Especially when we sketch, because our eyes constantly capture the dynamics of objects, we need to grasp the size and proportion of the picture with the help of the touch of our hands. Secondly, we should pay attention to the area occupied by the shape on the screen and its position relationship with the edge of the paper, which involves the balance of composition and the handling of dynamic elements. In addition, the relationship between light and shade and black and white is also an important reason for composition. At this stage, we mainly scrutinize and choose by drawing a small draft of the composition. Many painters waste energy repeatedly because they don't pay attention to composition. If the drawing is small, it can be solved by cutting it, but if it is big, there is no way. Therefore, it is important to pay special attention to the fact that when painting a manuscript, you must write a composition according to the actual proportion of the paper.
Step 4: Draw the overall relationship. After determining the composition, position the composition according to the small draft on the drawing paper, and then start drawing the overall relationship. At this stage, the eyes should not stay too much in the local part of the object, but should pay attention to the big relationship. The first is the relationship between form-finding. Complex shapes are summarized by simple geometric shapes, and the proportion, perspective and structural relationship of shapes are formed by straight lines. If it is a light and dark sketch, the auxiliary line should be as light as possible. Light-shade sketch should determine the big light-shade relationship at this stage, and don't be confused by the subtle changes of light and shadow. We often see painters squint at objects, which is a good way to find the relationship between big black and white. While drawing the relationship between light and shade, we should repeatedly adjust the relationship between shape and shape to be as accurate as possible. In addition, more importantly, the sense of overall relationship captured at this stage should be kept to the end.
Step 5: Deep shaping and overall adjustment. After the overall relationship is initially established, it is necessary to start to go deep into the picture. The so-called in-depth is not to depict the parts blindly, but to coordinate the shaping of the parts and the adjustment of the whole, so that the overall relationship is gradually deepened, and the knot, body, light and dark effects of objects and the expression of space, color and material sense are more clear and definite. Local construction does not need to be put in place at one time, and it is often necessary to adjust the overall relationship to take care of the relationship between the parts. The local preparation and deepening are carried out at the same time, which is convenient for grasping the overall relationship. The adjustment of the overall relationship can keep the picture intact, make the short-term operation accurate and vivid, and make the long-term operation rigorous and in-depth.
The specific drawing steps of the structure diagram are as follows.
(1), all-round observation to understand the spatial position and morphological characteristics.
(2) Structural analysis and perspective analysis.
(3) Draft, general position, spatial form and perspective relationship.
(4) Further affirm the morphological characteristics and transparently show the surplus and deficiency.
(5), adjust the overall picture.
The basic principle of sketch is the basic means to practice modeling ability, and it is also a simple photographic appearance of training and making objects, that is, through the eyes to the parts.