SER431 Lecture 21

Transcript

1. jgs SER 431 Advanced Graphics Lecture 21: Non-Uniform Rational Basis

   Splines III Javier Gonzalez-Sanchez javiergs@asu.edu PERALTA 230U Office Hours: By appointment

2. jgs Quiz 06 NURBS Solution

3. Javier Gonzalez-Sanchez | SER431 | Fall 2018 | 2 jgs

   Problem A https://github.com/javiergs/SER431/blob/master/Lecture20/nurbs_surface_controlled.cpp

4. Javier Gonzalez-Sanchez | SER431 | Fall 2018 | 3 jgs

   Problem A // NURBS // How many curves? How many control points per curve? // How many knots per curve? How many knots per inter-curve connection? // Order for U and V? // Offset for U and V? GLfloat ctlpoints[4][4][3] = { { { 20, 0, 20 } ,{ 0, 0, 20 },{ 0, 0, 20 } ,{ -20, 0, 20 } }, { { 20, 0, 0 } ,{ 0, 20, 0 },{ 0, 20, 0 } ,{ -20, 0, 0 } }, { { 20, 0, 0 } ,{ 0, 20, 0 },{ 0, 20, 0 } ,{ -20, 0, 0 } }, { { 20, 0, -20 } ,{ 0, 0, -20 },{ 0, 0, -20 } ,{ -20, 0, -20 } } }; GLfloat uknots[8] = { 0.0, 0.0, 0.0, 0.0, 3.0, 3.0, 3.0, 3.0 }; GLfloat vknots[8] = { 0.0, 0.0, 0.0, 0.0, 3.0, 3.0, 3.0, 3.0 };

5. Javier Gonzalez-Sanchez | SER431 | Fall 2018 | 4 jgs

   Problem B https://github.com/javiergs/SER431/blob/master/Lecture20/nurbs_surface_controlled.cpp

6. Javier Gonzalez-Sanchez | SER431 | Fall 2018 | 5 jgs

   Problem B // NURBS // How many curves? How many control points per curve? // How many knots per curve? How many knots per inter-curve connection? // Order for U and V? // Offset for U and V? const int V_size = 9; const int U_size = 7; const int ORDER = 4; GLfloat ctlpoints[U_size][V_size][3] = { { { 0, -4, 0 }, { -4, -4, 0 } ,{ -4, 0, 0 }, { -4, 4, 0 }, { 0, 4, 0 }, { 4, 4, 0 }, { 4, 0, 0 }, { 4, -4, 0 }, { 0, -4, 0 } }, { { 0, -2, 4 }, { -2, -2, 4 } ,{ -2, 0, 4 }, { -2, 2, 4 }, { 0, 2, 4 }, { 2, 2, 4 }, { 2, 0, 4 }, { 2, -2, 4 }, { 0, -2, 4 } }, { { 0, -4, 8 }, { -4, -4, 8 } ,{ -4, 0, 8 }, { -4, 4, 8 }, { 0, 4, 8 }, { 4, 4, 8 }, { 4, 0, 8 }, { 4, -4, 8 }, { 0, -4, 8 } }, { { 0, 0, 10 }, { 0, 0, 10 } ,{ 0 , 0, 10 }, { 0, 0, 10 }, { 0, 0, 10 }, { 0, 0, 10 }, { 0, 0, 10 }, { 0, 0, 10 }, { 0, 0, 10 } }, { { 0, -1, 12 }, { -1, -1, 12 } ,{ -1, 0, 12 }, { -1, 1, 12 }, { 0, 1, 12 }, { 1, 1, 12 }, { 1, 0, 12 }, { 1, -1, 12 }, { 0, -1, 12 } }, { { 0, -2, 14 }, { -2, -2, 14 } ,{ -2, 0, 14 }, { -2, 2, 14 }, { 0, 2, 14 }, { 2, 2, 14 }, { 2, 0, 14 }, { 2, -2, 14 }, { 0, -2, 14 } }, { { 0, -4, 16 }, { -4, -4, 16 } ,{ -4, 0, 16 }, { -4, 4, 16 }, { 0, 4, 16 }, { 4, 4, 16 }, { 4, 0, 16 }, { 4, -4, 16 }, { 0, -4, 16 } } }; GLfloat vknots[V_size + ORDER]= {0.0, 0.0, 0.0, 0.0, 2.0, 4.0, 4.0, 4.0, 6.0, 8.0, 8.0, 8.0, 8.0 }; GLfloat uknots[U_size + ORDER]= { 0.0, 0.0, 0.0, 0.0, 1.0, 3.0, 5.0, 6.0, 6.0, 6.0, 6.0 };

7. jgs Surfaces using OpenGL Support Animation

8. Javier Gonzalez-Sanchez | SER431 | Fall 2018 | 7 jgs

   Screenshot https://github.com/javiergs/SER431/blob/master/Lecture19/nurbs_flag.cpp

9. Javier Gonzalez-Sanchez | SER431 | Fall 2018 | 8 jgs

   Code #define V_NUMPOINTS 4 #define U_NUMPOINTS 4 #define V_NUMKNOTS (V_NUMPOINTS + 4) #define U_NUMKNOTS (U_NUMPOINTS + 4) // Knots GLfloat sknots[V_NUMKNOTS] = { 0., 0., 0., 0., 1., 1., 1., 1. }; GLfloat tknots[U_NUMKNOTS] = { 0., 0., 0., 0., 1., 1., 1., 1. }; // Control points - the Z values will be modified to make it wave GLfloat ctlpoints[V_NUMPOINTS][U_NUMPOINTS][3] = { { { 0., 3., 0. },{ 1., 3., 0. },{ 2., 3., 0 },{ 3., 3., 0. } }, { { 0., 2., 0. },{ 1., 2., 0. },{ 2., 2., 0 },{ 3., 2., 0. } }, { { 0., 1., 0. },{ 1., 1., 0. },{ 2., 1., 0 },{ 3., 1., 0. } }, { { 0., 0., 0. },{ 1., 0., 0. },{ 2., 0., 0 },{ 3., 0., 0. } } };

10. Javier Gonzalez-Sanchez | SER431 | Fall 2018 | 9 jgs

    // wave the flag by rotating Z cords though a sine wave void display() { for (int i = 1; i< 4; i++) for (int j = 0; j< 4; j++) ctlpoints[i][j][2] = sin((GLfloat)i + angle); angle += 0.1; gluBeginSurface(nurbsflag); gluNurbsSurface(nurbsflag, V_NUMKNOTS, sknots, U_NUMKNOTS, tknots, 3 * U_NUMPOINTS, 3, &ctlpoints[0][0][0], 4, 4, GL_MAP2_VERTEX_3); gluEndSurface(nurbsflag); }

11. jgs Quiz 07

12. Javier Gonzalez-Sanchez | SER431 | Fall 2018 | 11 jgs

    Screenshot https://github.com/javiergs/SER431/blob/master/Lecture08/reflection.cpp

13. Javier Gonzalez-Sanchez | SER431 | Fall 2018 | 12 jgs

    Instructions 1. Join the program for Shadows and Reflection (with the 3 boxes in a plain) 2. Add to the program one flag in a staff 3. Make the flag move (as shown before) 4. Show the shadow of the staff and the shadow of the flag 5. Show the reflection of the staff and the reflection of the flag

14. jgs SER431 Advanced Graphics Javier Gonzalez-Sanchez javiergs@asu.edu Fall 2018 Disclaimer.

    These slides can only be used as study material for the class SER431 at ASU. They cannot be distributed or used for another purpose.