CAP 5725
Computer Graphics I : Fundamentals of Computer Graphics 
Spring 2003

Last Updated:  26 April 2003.
Highlights: Final Test results available. Bonus submission deadline is Monday, April 28.

• Projects and Home Work 40%
• Programming language for the project: C/C++.
• Graphics API to be used: OpenGL and GLUT

• 2 Short tests (10% each, total 20%). Dates: January 29, March 26. 
• 2 Term exams (20% each, total 40%) Dates: February 24,  April 23.

Lectures :

Week1 ( Jan 6, Jan 8)

• Jan 6 : Introduction

• Historical Time Line of Computer Graphics and Animation
• History of Computer Graphics
• Computer Graphics in Films
  
• Jan 8 : Math for Computer Graphics.
• Today we covered some fundamentals Math. Read Chapter 2 of Shirley.
• Additional matter posted in WebCT.
• 1st Programming assignment posted today.

Week2 ( Jan 13, Jan 15)

• Jan 13: More Math
• Covered some interesting Math Problems.  Segment-Segment intersection, Convex or Non-convex testing, Point inside polygon testing
• Discussed a  plane-sweep algorithm (scan line algorithm) for finding intersection points for n line segments in O((n+k) log n) time.

• Jan 15: Programming using OpenGL
• for What is OpenGL? Why you need it? Where to get its? see  http://www.opengl.org/users/about/index.html
• for OpenGL overview, documentation, tutorials see http://www.opengl.org/developers/, http://nehe.gamedev.net/
• for GLUT documentation see http://www.opengl.org/developers/documentation/glut/ and for a tutorial see http://www.lighthouse3d.com/opengl/glut/

Week3 ( Jan 20, Jan 22)

• Jan 20: Martin Luther King, Jr. day

• Jan 22 : Transformations
• 2nd Programming assignment Due today.

Week4 ( Jan 27, Jan 29)

• Jan 27: Viewing
• for a good introduction to viewing: http://www.cs.brown.edu/stc/summer/viewing_history/viewing_history_1.html
• Jan 29: First short test today.
• 3rd Programming assignment submitted today.
  

Week5 ( Feb 3, Feb 5)

• Feb 3: Viewing and clipping
• Feb 5: Rasterization algorithm or scan-conversion algorithms

Week6 ( Feb 10, Feb 12)

• Feb 10: Visible Surface algorithms: Painter's algorithm, Painter's algorithm using BSP Tree, Z-buffer algorithm
• 4th programming assignment submitted today
• BSP Tree FAQ: http://www.gamedev.net/reference/articles/article657.asp or http://www.gamers.org/dhs/helpdocs/bsp_faq.html
• BSP Tree applet : http://symbolcraft.com/graphics/bsp/index.html
• Feb 12: Visible Surface algorithms: Ray Casting
  

Week7 ( Feb 17, Feb 19)

• Feb 17:  Reflection models and shading
• Feb 19:   Reflection models and shading

Week8 ( Feb 24, Feb 26)

• Feb 24:  Midterm Exam
• Feb 19:   Reflection models and shading

Week9 ( Mar 3, Mar 5)

• March 3:  Texture mapping
• March 5:   Texture Mapping, Bump mapping
  

Week10 ( Mar 10, Mar 12)

• March 3:  Sampling and antialiasing
• March 5:   Shadows: Shadow mapping

Week11 ( Mar 17, Mar 19)

• Spring Break
  

Week12 ( Mar 24, Mar 26)

• March 24:  Ray Tracing
• March 25:   Second short test
  

Week13 ( Mar 31, Apr 2)

• March 31:  Ray Tracing (continued)
• April 2:   Radiosity
• Online Radiosity Tutorial
  

Week14 ( Apr 7, Apr 9)

• April 7:  Radiosity (continued)
• April 9:  Curves and Surfaces

Week15 ( Apr 14, Apr 16)

• April 14:  Curves and Surfaces (continued)
• April 16:  Color 

Week16 ( Apr 21, Apr 23)

• April 14:  Color (continued)
• April 16:  Final exam.

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HomeWork/Projects:

• On the average one homework/project per week. 
• Unless specified otherwise, every assigned homework or project will be due exactly 1 week from the submission date. Submissions are due before the class time on the submission date.
• Submission will be accepted through WebCT.
• Complete project, with source code, executable and sample images must be submitted on or before the deadline.
• WebCT will not allow submission after the set time.
• No credit for late submission.
• Students will be allowed to make up to half of the project credits (20%) by submitting bonus projects.
• Each student will work independently on the project(s).
  
• NOTE: Student will not submit code written by someone else (or downloaded from internet). Student submitting other's work will not receive any credit and such action will be reported to the graduate committee chair.

• Programming Assignment 1: Posted on Wednesday, Jan 8. Due: Wednesday, Jan 15.

• Write a C program to take a polygon and a point as input and output “convex” or “not convex” based on whether the input polygon is convex and, if the polygon is convex, “inside” or “outside” based on whether is the point is inside the convex polygon or outside.(NOTE: Polygon is input as #of vertices, followed by float pairs, one for each vertex. Make your executable to accept input from Standard Input.)

• Programming Assignment 2: Posted on Wednesday, Jan 15. Due: Wednesday, Jan 22.

• Compile and execute “Simple program” program described in the class
• Add double buffering
  use glOrtho to specify an world extent of [-10 10 -10 10]
  Before glInit() function is called read in a number of line segments.
• (Input format: # of line segments. Followed by end points (x1 y1 x2 y2) of each line segment. One line segment data per line.
  Modify the “display” callback function to draw a segments and highlight their intersection points. (NOTE: You may use any intersection algorithm)
  Due: Wednesday, Jan 22.
• Bonus project: Modify the 2nd assignment to
  Solve the segment-segment intersection using Plane-sweep Algorithm
  Animate the plane sweep algorithm. Show how of the line sweeps though the plane and changes to the event queue and status list as it sweeps the plane.
  Highlight the intersection points.
  Note: It is worth one regular assignment. Due on Monday, Jan 27

• Programming Assignment 3: Posted on Monday, Feb 3. Due: Monday, Feb 10. 

• Write a walkthrough application to move around a polygonal scene. Use arrow keys to navigate. Input a polygonal scene of your choice. Provide a toggle between parallel and perspective projection (use key 'p'). 
• Experiment with OpenGL gluLookAt and glOrtho/glPerspective function. (55%)
  Finally substitute the functions with your own LookAt, Ortho, Perspective functions. (45%) 
• Due: Monday, Feb 10

• Programming Assignment 4: Posted on Monday, Feb 10. Due: Wednesday, Feb 19.

• Write a OpenGL program to render a polygonal scene with object visibility problem handled by enabling OpenGL's Z-buffer support.
• Replace OpenGL rendering by your own rendering routine. Provide a toggle to substitute the display code using OpenGL function calls with  your own rendering code.
• Note that OpenGL does not provide facility to replace its rasterization/Z-buufer  routine with your own. In order to be able to do your own rendering, you will create your own raster and display raster using the following code.
• void display(void) {
  … render your scene on to the raster
      glRasterPos2i(0,0);
      glDrawPixels(cols,rows,GL_RGB,GL_FLOAT,raster);
  …
  }
  void reshape(int w, int h)
  {
      glViewport(0,0,(GLsizei)w,(GLsizei)h);
      glPixelZoom(w/cols,h/rows);
      glMatrixMode(GL_PROJECTION);
      glLoadIdentity();
      glOrtho(0, w, 0, h, -1 , 1);
  }
  raster = (float*)malloc(cols*rows*3*sizeof(float));
  
• Here is a sequence of operations to do inside the display for implementing your own Z-buffer renderer: 
• Compute view transformation (compute view matrix)
• Compute projection matrix fromt the projection specification,
• Compute a transformation to map the projection view volume to a volume whose top-left is (0,0) and bottom-right is (rows-1, cols-1).
• Multiuply these 3 matrices and create one single transformation matrix (T)
• For every triangle
• transform its vertices using transformation matrix T
• Clipping should go here. For this project you do not have to do clipping.
  
• Scan convert the triangle. If the pixel (x,y) values are within (0,0) and (rows-1, cols-1) then compare its z-value with the Z-buffer(x,y). If the z-value is smaller that Z-buffer z-value then write the pixel and update the Z-buffer.
• Note for this project you have to input your scene information. Create your own list of polygons. Your scene should have at least a couple of triangles of different color and one of the triangles should be partially visible to the view point. You may write your own parse to import scene data created by a modeler. Here is a scene data for a toy plane (in triangles) written in simple nff format. Writing a parser for this format should be very simple. Try out.
• Due: Wednesday, Feb 19.

• Programming Assignment 5: Posted on Tuesday, Feb 25. Due: Wednesday, March 5.

• Extend project 4 to compute color at the triangle vertices. 
• Define one or more light sources. Light source definition requires Position and/or  Direction with cartesian components defined in the world co-ordinate system.
• Use Diffuse and phong reflection model to compute the color.
• Carry out the computation at every vertex after viewing transformation (before projection).
• Compare your lighting computation and OpenGL lighting computation. 
• Help for OpenGL functions calls for lighting is available in webCT page "OpenGL Lighting Support" .
• 50% of the grades are for OpenGL lighting computation and 50% of grades are for your own lighting computation.