SER332 Lecture 18

Introduction to Graphics and Game Development
Mesh Data Structure II
(201804)

Transcript

1. jgs SER332 Introduction to Graphics and Game Development Lecture 18: Mesh Data Structure II Javier Gonzalez-Sanchez javiergs@asu.edu PERALTA 230U Office Hours: By appointment
2. jgs Plane, Cylinder, and Box
3. Javier Gonzalez-Sanchez | SER332 | Spring 2018 | 3 jgs Creating a Triangulated Plane // Generate vertices in XZ-plane for i = 0 to n for j = 0 to n Create vertex at location (i*xsize, 0, j*ysize) // step 2. Generate indices for i = 0 to ? Create triangle with indices(i, i+1, i+n+1) Create triangle with indices( i+1, i+n+2, i+n+1) xsize ysize vn v0 v1 v n+1 vn+2
4. Javier Gonzalez-Sanchez | SER332 | Spring 2018 | 4 jgs Creating a Triangulated Plane // creating a triangulated plane Mesh* createPlane(int arena_width, int arena_depth, int arena_cell) { Mesh *me = new Mesh; int n = arena_width / arena_cell; int m = arena_depth / arena_cell; // vertices for (int i = 0; i<n; i++) { for (int j = 0; j < m; j++) { me->dot_vertex.push_back(Vec3<GLfloat>(i*arena_cell, 0.0, j*arena_cell)); } } // faces for (int i = 0; i<(n*m) - m; i++) { if ((i + 1) % n == 0) continue; me->face_index_vertex.push_back(i); me->face_index_vertex.push_back(i + 1); me->face_index_vertex.push_back(i + n); me->face_index_vertex.push_back(i + 1); me->face_index_vertex.push_back(i+ n + 1); me->face_index_vertex.push_back(i + n); } return me; }
5. Javier Gonzalez-Sanchez | SER332 | Spring 2018 | 5 jgs Creating a Triangulated Plane § Use colors to verify right-hand rule.
6. Javier Gonzalez-Sanchez | SER332 | Spring 2018 | 6 jgs Creating a Triangulated Cylinder // Generate vertices on top for i = 0 to n angle = (i*360) / (n+1) create vertex at (cos( angle), height, sin(angle)) // Generate vertices on the bottom // same process but height = 0 // Generate vertex in the middle of the top // Generate vertex in the middle of the bottom // Generate triangles on top // Generate triangles on the bottom // Generate triangles on the side v1 Vn+2 v0 Vn+1
7. Javier Gonzalez-Sanchez | SER332 | Spring 2018 | 7 jgs Creating a Triangulated Cylinder // create a triangulated cylinder Mesh* createCylinder(int h, int radio) { int n = 100; double angle; Mesh *m =new Mesh; // Generate vertices on top m->vertex.push_back(Vec3<GLfloat>(0.0, h, 0.0)); for (int i = 0; i<n; i++) { angle = (M_PI/180)*(1.0*i*360)/n; m->vertex.push_back(Vec3<GLfloat> (cos(angle)* radio, h, sin(angle)* radio)); } // Generate vertices on bottom for (int i = 0; i<n; i++) { angle = (M_PI/180)*(i*360)/n; m->vertex.push_back(Vec3<GLfloat> (cos(angle)* radio, 0.0, sin(angle)* radio)); }
8. jgs Javier Gonzalez-Sanchez | SER332 | Spring 2018 | 8 // Generate triangles on top for (int i = 1; i<=n; i++) { m->vertexIndex.push_back(0); m->vertexIndex.push_back(i); if (i==n) { m->vertexIndex.push_back(1); }else{ m->vertexIndex.push_back(i+1); } } // There is no bottom. Use the floor. // Generate triangles on the side for (int i = 1; i<=n; i++) { m->vertexIndex.push_back(i); m->vertexIndex.push_back(n+i); if (i!=n) { m->vertexIndex.push_back(n+i+1); } else { m->vertexIndex.push_back(n+1); } m->vertexIndex.push_back(i); if (i!=n) { m->vertexIndex.push_back(i+1); m->vertexIndex.push_back(n+i+1); }else{ m->vertexIndex.push_back(1); m->vertexIndex.push_back(n+1); } } return m; }
9. Javier Gonzalez-Sanchez | SER332 | Spring 2018 | 9 jgs Creating a Triangulated Cylinder
10. Javier Gonzalez-Sanchez | SER332 | Spring 2018 | 10 jgs Creating a Triangulated Cube // Generate vertices on top // Generate vertices on the bottom // Generate triangles on top // Generate triangles on the bottom // Generate triangles on the sides
11. Javier Gonzalez-Sanchez | SER332 | Spring 2018 | 11 jgs Creating a Triangulated Cube
12. Javier Gonzalez-Sanchez | SER332 | Spring 2018 | 12 jgs Source Code § https://github.com/javiergs/SER332/blob/master/Lecture18/main.cpp
13. Javier Gonzalez-Sanchez | SER332 | Spring 2018 | 13 jgs Test Yourselves § Include methods to create cubes, planes, and cylinders § Include methods to create spheres
14. jgs SER332 Introduction to Graphics Javier Gonzalez-Sanchez javiergs@asu.edu Spring 2018 Disclaimer. These slides can only be used as study material for the class SER332 at ASU. They cannot be distributed or used for another purpose.