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Politecnico di Milano, DEIB September 25th, 2014 Course 090958 Computer graphics M. Gribaudo First Name - Nome: ................................................... Family Name - Cognome: ............................................. ID - Matricola: ................................... IMPORTANT: • An answer in order to be considered valid must show all computations involved in obtaining the results. This will make it easier to find the mistakes (if any) and will help the grader to assign partial credit. Una risposta per essere considerata valida deve riportare TUTTI i passaggi algebrici necessari per il calcolo delle soluzioni. • Pencils are allowed. È possibile usare la matita. • No cell phones can be used! No electronic devices, except pocket calculators are allowed. I telefoni cellulari non possono essere usati per nessun motivo. Non è consentito l’uso di alcun dispositivo elettronico, eccetto le calcolatrici tascabili. • It is possible to answer in Italian. È possibile (e consigliabile per i madre-lingua) rispondere in italiano. 1 2 3 Tot Exercise 1 Consider the following mesh: Considering that floating point numbers occupies 4 Bytes, and integer indices 2 Bytes, a) Encode the mesh with a triangle list. Determine the memory occupancy. b) Encode the mesh using a triangle strip. Determine the memory occupancy. c) Encode the mesh using a triangle list, with vertex and index buffers. Determine the memory occupancy. d) Given that point A is projected on screen at coordinate y=100 and point F is projected on screen at y = 150 , determine the uv coordinates of the point on segment AF at y=135 using perspective correct interpolation. Solution: a) List: {0, 0, 0.5, 0, 0.5 , 0.2, 0, 0.7, 0.2, 0.9 , 0.4, 0.3, 0.5 , 0.4, 0.5 , 0.2, 0, 0.7, 0.2, 0.9 , 0.4, 0.3, 0.5 , 0.4, 0.5 ,…