Computer Graphics

Welcome back to
Computer Graphics course
 How was your holidays?
 Today is homework 1deadline
 Bring your results in one page to TA’s desk
 Your name/Student No./course ID
 input.txt.000.png - input.txt.012.png
Computer Graphics
 submit your implementation from http://goo.gl/OF0i0b
1st quarter, 2015
 Do NOT despair !
諦めんなよ！どうしてそこでやめるんだ！
Nara Institute of Science and Technology
May 7, 2015
 Close the site tonight.
 We are still open submission with small deduction.
You can contact us for further support.
 But, we need to go ahead in this class…
Today’s topics
Homework 2
 Homework 2 is due next week
 due May 21, 2015.
 Homework 3 pre-out
 Print out the results in one page
 Your name / Student No. /course ID
 Check your understanding
 Homework 2 support
 demo.txt.input.txt.000.png - demo.txt.input.txt.012.png
 Submit your source codes from http://goo.gl/ZqP7LK
in my implementation,
 about 30 lines on light.frag.glsl
 12 lines on display.cpp
 10 lines on readfile.cpp
 about 15 lines on Transform.cpp
Next homework - edX
(recap)
What’s required in Homework 2 ?
 Unit 2
 This requires you
 Lecture 7: OpenGL Shading
 Remains (L7V3,V4),
about 30 min.
 Lecture 8: OpenGL 2
 five clips,
about 30 min.
 to read a scene from file
 ≤ 10 objects with configurable material
 ≤ 10 lights (point/directional)
 to change viewpoint
 Rotation (as in HW1) / translation / scale
 to render the objects according to their material
 Implement the above using OpenGL!
 Start early! It takes
hours!
1
What’s in skeleton code?
Detailed explanation
about Homework 2
File
main.cpp
variable.h
shaders.h / shaders.cpp
Transform.h /
Transform.cpp
readfile.h / readfile.cpp
display.cpp
shaders/light.vert.glsl
shaders/light.frag.glsl
contents
core functions
variables used in the program
prepare shaders
Transform class
implements geometric
transforms
parser for input file
display() for render the scene
vertex shader
fragment shader
What’s required?
Transform.cpp
- Tranform class
 You need to fill codes to “YOUR CODE FOR HW 2 HERE.”
 Form 4 × 4 geometric transformation matrix
 Transform.cpp
 Implement geometrical transformations
 mat4 lookAt(const vec3 &eye, const vec3 &center, const vec3 &up)
 mat4 perspective(float fovy, float aspect, float zNear, float zFar)
 Similar to HW1
 mat4 scale(const float &sx, const float &sy, const float &sz)
 Rotations, translations, scales, perspective projection.
 mat4 translate(const float &tx, const float &ty, const float &tz)
 readfile.cpp
 for reading the input file
 display.cpp
 displaying the scene.
 shaders/light.frag.glsl
 mat3 rotate(const float degrees, const vec3& axis)
 This is also used in the followings as helper function.
 Change viewpoint
 void left(float degrees, vec3& eye, vec3& up)
 void up(float degrees, vec3& eye, vec3& up)
 fragment shader to implement phong shading
readfile.cpp
- read scene file
push/pop Transform
 Specifications
 example)
 https://courses.edx.org/courses/BerkeleyX/CS_184.1x/3T2
014/courseware/Unit_2/Homework_2/
 Read parameters, set them to variables
 light / camera command
 Check variable.h to find variables to be set
 Process transformation stack – use Tranform class
 translate / scale / rotate command
pushTransform
translate -0.4 -0.4 0
pushTransform
translate 0 0 0.6
sphere 0.1
popTransform
scale 0.2 0.2 .5
translate 0 0 0.5
cube 1.0
popTransform
 Perform transformation on transfstack.top()
 Do you know “stack”, one of the data structures?
2
display.cpp
shaders/light.frag.glsl
 Pass some values to the shader by glUniform*()
 Refer shaders/light.frag.glsl in HW1
 light positions and colors
 Remember that light positions must be transformed by
modelview. Transformvec(…) funcation helps do it.
 object transformations & material properties
 Set up the net transformation matrix for the objects.
 Core process is already implemented in it
 Extend it to accept lighting setting from input
 Directional / pointlight
 Up to 10 lights
 Set transf by using mv(modelview),
sc(scale) & tr(translation) specified by keyboard input.
Homework 3 pre-out
 There are three options
Questions?
 [beginner] HW3.1
 Requirements are much smaller than the one on edX.
 [intermediate] HW3.2
 [advanced] HW3 (original version on edX)
 You can use skeleton made by Kubo-sensei.
 Download from the course website.
http://omilab.naist.jp/~funatomi/courses/CG/2015/
 Due May 28, 2015.
Please tell us your ID & name
before asking/answering.
 Homework support on May 21, 28.
Check!
Take a short test from
http://goo.gl/yRaXQw
Questions?
Please tell us your ID & name
before asking/answering.
3
Homework 2
Questions?
 due May 21, 2015.
 Print out the results in one page
 Your name / Student No. /course ID
 demo.txt.input.txt.000.png - demo.txt.input.txt.012.png
 Submit your source codes from http://goo.gl/ZqP7LK
in my implementation,
Please tell us your ID & name
before asking/answering.
 about 30 lines on light.frag.glsl
 12 lines on display.cpp
 10 lines on readfile.cpp
 about 15 lines on Transform.cpp
Next homework - edX
 Unit 2
 Lecture 7: OpenGL Shading
 Remains (L7V3,V4),
about 30 min.
 Lecture 8: OpenGL 2
 five clips,
about 30 min.
4