Solve for missing side of triangle

Here, let's say that the UV solution of each pixel in rasterize is actually done with the barycentric coordinates. The barycentric coordinates represent a weight, that is, with the barycentric coordinates, the properties of a certain point on the triangle can be obtained by the weighted average of three vertices. The third model of the triangular pyramid receiving ball is to determine the star to construct a right triangle. This model usually appears in the center of a curved regular triangle in the triangular pyramid of a postal triangle. By connecting the vertex and the center of the triangular pyramid, we can get that the height of the triangular pyramid is perpendicular to the bottom. At this time, the center of the circumscribed ball is on the high line, so the radius of the circumscribed ball of the right triangle can be solved according to the Pythagorean theorem. The key of this model is to determine the center of the ball by using the extraterrestrial of the regular triangle on the bottom, and then construct a triangle to convert the three-dimensional figure into a planar figure, and find the radius of the ball in the right triangle. Finally, it's time to discuss triangle filling. The general idea is to establish an bounding box according to the maximum pixel coordinates of the three vertices of the triangle, scan in the bounding box line by line, and judge whether each pixel is in the triangle. But it is still not good to start the operation directly: for some pixels that pass through the three sides of the triangle, the algorithm will conclude that they are not inside the triangle, but they also need to be filled, otherwise there will be jagged on the model. As shown in the figure, the triangle will only fill the pixels marked in pink, and the filling is missing: Finally, there are three special segments of the triangle, namely the centerline, bisector and height. These three line segments play an important role in triangles. The middle line of a triangle. Divide the bottom edge into two equal line segments, and the areas of the divided triangles are equal. The angle bisector of a triangle divides the top angle of the triangle into two equal angles, and is equal to half of the original angle. In addition to calculating the area of the triangle, the height of the triangle also constructs two right triangles, which provides favorable conditions for solving the angles of other angles. If there are three special line segments, triangles, in doing the problem, we can carry out simple derivation to match other conditions in the problem. The thinking and skills of solving the problem are also very simple. We can use the relationship of the three sides of a triangle. The sum of any two sides is greater than the third side, and the difference between any two sides is less than the third side. This relationship can solve that the range of the third side is in the middle of the known difference between the two sides and the sum of the two sides. After obtaining this range, we should also pay attention that the two sides of this range cannot take equal signs. Through the relationship of this layer, the relationship between the longest side, the shortest side or the perimeter of the triangle can be solved. In short, the circumscribing ball of the triangular pyramid needs to be converted according to the specific situation of the tricycle cone or it can not be better converted into what we know. The relevant knowledge of cuboid, triangular prism or regular triangle is combined with Pythagorean theorem to solve. In learning, we need to understand the forms of these three models clearly, and finding the way to solve the problem and construct the model of each model is the core method to solve the triangular pyramid circumscribing ball. For example, the ways to find the equal quantity relationship in junior high school mainly include the Pythagorean theorem, the proportional line segment of the parallel line section, the similarity of triangles, and the equal area method. Finding the definition domain is mainly to find the special position (limit position) of the figure and solve it according to the analytical formula. The final exploration problem is ever-changing, but it is necessary to analyze and study the figure, and use geometric and algebraic methods to find the value of X.