Welcome to the Computer Graphics Unit for 2020
Weekly Workbooks will be released incrementally throughout the teaching block.
Template project to test SDL
run with make
Project to demsonstrate pixels and drawing. Output shows two windows
- interpolation of grey values (from 0 to 255) along the x axis and displaying this in an output along the whole y axis
- two dimensional colour interpolation starting with 4 solid colours in 4 corners and interpolating between them, first the left most and right most columns and taking this as the values to interpolate along the x axis
run with make
Project to demonstrate line drawing and subsequently triangle drawing (drawing lines between three CanvasPoints), filling and texture mapping.
run with make
u draws random colourful outlined triangles within the drawing window
f draws random colourful filled triangles within the drawing window
t draws a triangle with the texture from texture.ppm mapped onto it
Project to demonstrating loading of .obj and .mtl files and projecting them on a 2D image plane using rasterising
- first with a wireframe using a previous project's
draw_trianglefunction - then by filling the triangles, also using a previous project's
fill_trianglefunction. - then by projecting the triangles with the correct depth by using a depth buffer, taking into account the distance from the camera
run with make
Project to demonstrate navigation and transformation of a 3D space projected on a 2D plane
- first the floor of the cornell box is textured using the same
texture.ppmfrom week 3 - being able to move the camera position using translation
- being able to move the camera position using rotation
- orbiting the cornell box while having the camera always look at the origin
run with make
w a s d to move forwards, left, back and right respectively within the cornell box
page_up page_down to move up and down respectively
q e to rotate around y axis left and right respectively
0 9 to rotate around x axis up and down respectively
left right up down arrow keys to move camera (look) left, right, up and down respectively
z x to rotate around z axis (up and down) respectively
l to look at origin at any time
o to start orbiting (in y axis) around origin
r to reset the camera view
Project to demonstrate the raytracing method of projecting 3D points onto a 2D image plane. For the whole image plane rays are projected out and the closest triangle interaction with that ray is found and the colour is set
Additionally shadows are now possible from setting a light source, again from every point on the 2D image plane, a 3D ray is cast from the surface to the light and any interaction with another triangle means a shadow should be cast
run with make or make speedy for better results
1 2 3 to switch between raytracing, rasterising and wireframe rendering respectively
these are not recommended when in the raytracing rendering method, this is best achieved when in rendering method 2 or 3
w a s d to move forwards, left, back and right respectively within the cornell box
page_up page_down to move up and down respectively
q e to rotate around y axis left and right respectively
0 9 to rotate around x axis up and down respectively
left right up down arrow keys to move camera (look) left, right, up and down respectively
z x to rotate around z axis (up and down) respectively
l to look at origin at any time
o to start orbiting (in y axis) around origin
r to reset the camera view
Project to demonstrate various lighting effects on a raytraced projection of 3D points.
- proximity lighting, lights up surfaces with a scale depending on the distance to the light
- angle of incidence lighting, lights up surfaces depending on the angle at which the light hits it (i.e. higher angle means more light spread)
- specular lighting, given a scale factor, makes surfaces appear more shiny or more matte
- ambient lighting, lights up surfaces due to reflections from light off other surfaces
Ambient lighting is computationally expensive therefore a threshold minimum value of 0.3 illuminates the area even when no other lighting is turned on (e.g. from outside sources)
run with make or make speedy for better results
1 2 3 to switch between raytracing, rasterising and wireframe rendering respectively
4 5 6 to switch between no shading, gourad shading and phong shading respectively
p to toggle light position when in raytracing mode
NUM_8 NUM_2 NUM_4 NUM_6 to move the light forwards, backwards, left and right respectively
NUM_+ NUM_- to move the light up and down respectively
note. ambient lighting is always on
[ to toggle proximity lighting
] to toggle angle of incidence lighting
# to toggle shadows
' to toggle specular lighting
these are not recommended when in the raytracing rendering method, this is best achieved when in rendering method 2 or 3
w a s d to move forwards, left, back and right respectively within the cornell box
page_up page_down to move up and down respectively
q e to rotate around y axis left and right respectively
- +(=) to rotate around x axis up and down respectively
left right up down arrow keys to move camera (look) left, right, up and down respectively
z x to rotate around z axis (up and down) respectively
l to look at origin at any time
o to start orbiting (in y axis) around origin
r to reset the camera view and light position
A Project to demonstrate various modelling, rendering lighting and animation effects on a projection of 3D points.
There are various 3D .obj files included with this project, from a sphere and a simple cornell box and hackspace logo to an increasing complex environment combining these models.
cornell-box.obj contains the simple cornell box
cornell-shapes-<num>.obj contains the cornell box with an increasing number of other models as the appendix number increases
There are also some other misc cornell-box files used during development as well as the low-poly sphere and hackspace logo.
Each .obj file uses the same .mtl materials file for ease of use.
There are 3 different rendering options when running the program
- wireframe, draws a white outline around all the triangles in the model, creating a mesh. This rendering approach also displays the position of the light within the model
- rasterise, uses a line based interpolation approach to 'fill' triangles giving them a colour.
- raytrace, uses rays projected from the camera to each point in 3D space to find the intersected triangle to display on the 2D plane
- proximity lighting, lights up surfaces with a scale depending on the distance to the light
- angle of incidence lighting, lights up surfaces depending on the angle at which the light hits it (i.e. higher angle means more light spread)
- specular lighting, given a scale factor, makes surfaces appear more shiny or more matte
- ambient lighting, lights up surfaces due to reflections from light off other surfaces
Ambient lighting is computationally expensive therefore a threshold minimum value of 0.3 illuminates the area even when no other lighting is turned on (e.g. from outside sources)
To build and run this project use the included Makefile
$ make(recommended) or for better results
$ make speedyFor animation uncomment the following line inside main()
animate(t, window_grey, texture);1 2 3 to switch between raytracing, rasterising and wireframe rendering respectively
4 5 6 to switch between no shading, gourad shading and phong shading respectively
p to toggle light position when in raytracing mode (legacy, incompatible with soft shadow approach)
NUM_8 NUM_2 NUM_4 NUM_6 to move the light forwards, backwards, left and right respectively
NUM_+ NUM_- to move the light up and down respectively
note. ambient lighting is always on
[ to toggle proximity lighting
] to toggle angle of incidence lighting
# to toggle shadows
' to toggle specular lighting
these are not recommended when in the raytracing rendering method, this is best achieved when in rendering method 2 or 3
w a s d to move forwards, left, back and right respectively within the cornell box
page_up page_down to move up and down respectively
q e to rotate around y axis left and right respectively
- +(=) to rotate around x axis up and down respectively
left right up down arrow keys to move camera (look) left, right, up and down respectively
z x to rotate around z axis (up and down) respectively
l to look at origin at any time
o to start orbiting (in y axis) around origin
r to reset the camera view and light position