OPENGL PROJECT PRESENTATION SLIDES INTERFACE AND A

CASE STUDY

Serguei A. Mokhov and Miao Song

Concordia University, Montreal, Quebec, Canada

Keywords:

Slide presentations, 3D, OpenGL, Real-time, Frameworks, Shaders, Tidgets, GPU, Human-computer inter-

faces, Interaction, Computer graphics education.

Abstract:

We present a concept of a 3D interface to power-point-like presentations using OpenGL. We argue the pre-

sentations of such kind are a lot more useful to demonstrate projects, conference talks, or computer graphics

education tutorials and lectures with the results of 3D animation, effects, and others alongside with the pre-

sentation in place instead of switching between a regular presentation software to the demonstration and back

– the demo and the presentation are combined together in one unit and can serve as an educational piece on its

own.

1 INTRODUCTION

We present a re-usable open-source framework de-

signed and implemented in C++ for OpenGL-based

presentation slides. We position ourselves and argue

that such presentation tools are better suited for com-

puter graphics presentations be it a lecture, tutorial,

a project, or a conference talk on computer graph-

ics techniques than a generic power-point presenta-

tion done say in Impress (Sun Microsystems, Inc.,

2008) or PowerPoint (Microsoft, Inc., 2008) followed

by the demo. There are several reasons for this ar-

gument: one can show progressively a topic on some

computer graphic techniques with the immediate ef-

fects and the required animation, rendering, texture

mapping, shading, and other techniques while retain-

ing the expressiveness of power points. We brieﬂy

go over the visual design through an actual case study

and show some examples and argue why on may want

such a framework for their OpenGL (OpenGL Archi-

tecture Review Board, 2008; Angel, 2003; Woo et al.,

1999) project as opposed to the standard widespread

generic presentation software despite the fact it takes

(sometimes a lot) more effort to prepare such OpenGL

slides.

2 DESIGN AND CASE STUDY

The design of this OpenGL slide presentation frame-

work consists of two parts – the visual and the soft-

ware architecture. Further in this work we discuss

only the visual aspects of the design in some detail

and to save space omit the software design, which is

described in more detail in the related work (Mokhov

and Song, 2008) and the project’s documentation. We

discuss a use case the framework was applied to along

the way.

The actual ﬁnal “production” visual design as-

pects of the OpenGL-based slides are up to the par-

ticular programmer or artist that prepares the demo

together with the main concept. The presenter can set

up the main colors of the fonts, the text of the items

and the title bar, as well as the display of frame rate,

elapsed time, etc. as they see ﬁt in their overall theme.

The main body is the scene in each slide, poten-

tially with the animation, is completely determined

by the nature of the project’s scene itself and what is

being portrayed. The colors of the power points and

other textual widgets, which we call tidgets, can be

adjusted to match the main theme. All tidgets, can

be disabled from being displayed such that they don’t

clutter the slide screen if there is something happen-

ing at the main scene of that slide.

The framework also maintains support for the

optional vertex and fragment shaders (Rost, 2004;

Everitt, 2003; 3D Labs, 2004a; 3D Labs, 2004b),

which are popular among graphics community of

409

A. Mokhov S. and Song M.

OPENGL PROJECT PRESENTATION SLIDES INTERFACE AND A CASE STUDY.

DOI: 10.5220/0001820604090412

In Proceedings of the Fourth International Conference on Computer Graphics Theory and Applications (VISIGRAPP 2009), page

ISBN: 978-989-8111-67-8

Figure 1: OpenGL Slide Example 1.

Figure 2: OpenGL Slide Example 2.

GPU programmers and beyond.

One of the use-case is illustrated further through

some selected slides of an actual presentation. The

example project that uses the framework is the pre-

liminary real-time hair animation modeling done by

students (Mokhov, 2004) at the early stages of the de-

velopment as a progress report. The ﬁgures in this

work illustrate the examples of the framework’s usage

from that project (some select slides). The authors are

currently designing the equivalent presentation slides

for the Softbody Simulation System (Song and Gro-

Figure 3: OpenGL Slide Example 3.

Figure 4: OpenGL Slide Example 4.

gono, 2008) and the Open Stereoscopic Plug-in col-

lection (Loader et al., 2008) to further strengthen the

concept of the OpenGL slides and make it more us-

able.

Every slide comprises a scene that can feature

its own geometry hierarchy (usually in accordance

with the procedural modeling techniques (Wikipedia,

2007)), lighting setup (if necessary), texture map-

ping, pixel and vertex shaders (Various contributors,

NVIDIA Corporation, 2003; Various contributors,

Microsoft Corporation, 2003; Kilgard, 1999), or cus-

GRAPP 2009 - International Conference on Computer Graphics Theory and Applications

410

tom navigation keys. One can see the basic structure

of the slides: the slide title on the top left corner in

bold, followed by navigational help line how to move

between the slides, and some help on the default slide

keys at the bottom left, then some state information

about the status of the vertex and fragment shaders,

and the FPS (frames per second) and the elapsed time

metrics tidgets that are updated at run-time, and of-

ten are asked about to be shown while doing demo

to show how efﬁcient or inefﬁcient some real-time

graphics algorithms are.

In Figure 1 is an example of a simple scene with

a set of 3D meshes (that can be interacted with as in-

structed on the slide and to turn on the animation).

The slides in Figure 2, Figure 3, and Figure 4 show

progressively the increase the level of detail of the

graphical information shown on the slide scene from

that particular project (Mokhov, 2004).

The framework is designed to be source-code

portable, i.e. it can compile and produce a runnable

executable in Windows, Linux, and MacOS X plat-

forms, wherever OpenGL and C++ compiler are

available.

3 LIMITATIONS

One of the most obvious limitations of the presented

framework is the amount effort required to program

the slides and as a consequence the presenter has to

have some programming experience. Additionally, in

the current state the programming language restric-

tion is that of C++, so if the programmer designs the

project using another language, they currently have

do the required integration support themselves.

Some of these are mitigated as most of such pre-

senters are computer science professors and students

and teach an learn the graphics. Once a presenta-

tion set of slides created – it can serve both teaching

and learning purposes – to present it in class and if

the source code is made available to students to learn

gradually the techniques from the actual working ex-

amples, done in the presentations. Some other limita-

tions are to be resolved during the future work on this

project.

Another potential limitation of this work is that it

requires to be compiled into an executable that can-

not be edited on the spot without recompilation. It

also places the limitation on the presenter’s hardware

used in the classroom or a conference that should

have all the necessary libraries an drivers to run the

executables as well as perhaps a reasonable graph-

ics card. The software requirements and the corre-

sponding space here are however less stringent than

the complete ofﬁce installation or even PowerPoint

viewer and does not absolutely require administrative

privileges to install. It is also fair to assume at the

computer graphics events and classes the computers

have the necessary graphics card to enable proper pre-

sentations.

4 CONCLUSIONS

We have presented a framework for OpenGL-based

programs to make power-point like presentation in-

terfaces to projects as well as teaching and educa-

tion materials in computer graphics (Tenneson et al.,

2008; Talton, 2007) and beyond, where each slide

has a navigation capabilities and power points, and

things alike. It additionally includes an OpenGL-

based scene that can be interacted with within that

slide, with the GPU shader support and so on. The

framework allows the presenters to integrate their

computer graphics project with the presentation sav-

ing demo and presentation time to illustrate various

stages of the project evolution as well as demo them.

This idea can be further extended in providing em-

bedded manuals to the games and projects. While the

slides development may require more effort to pro-

duce as they are required to be programmed, they in-

tegrate much better and can express much better the

animation and modeling aspects, even with movies

and audio that OpenGL and its extensions allow with

the demo that other presentation software tools, such

as Microsoft Power Point (Microsoft, Inc., 2008) and

OpenOfﬁce Impress (Sun Microsystems, Inc., 2008)

cannot allow seamless integration with one’s own

projects while giving the presenter all of the control

and interaction they need to present their work.

Future Work. There are a number of items to im-

prove on in the framework to make it more usable and

adopted:

• Release the framework at CGEMS (Jorge et al.,

2008) and SIGGRAPH.

• Integrate with the Softbody Simulation Sys-

tem (Song and Grogono, 2008).

• Integrate with the OpenGL stereoscopic plugin-

framework (Loader et al., 2008).

• Add an optional GLUI interface for navigation

and control when not in the full-screen mode.

• Extend to other languages that support OpenGL,

e.g. Java, Python, and others.

• Export functions to export the presentation as a

sequence of images automatically in case it is ab-

OPENGL PROJECT PRESENTATION SLIDES INTERFACE AND A CASE STUDY

411

solutely necessary to produce static slides for in-

corporation into the regular presentation software.

• Allow for XML-based or .properties based

conﬁguration ﬁles to be imported and exported to

generate the slide content and instantiate the ap-

propriate scene, i.e. to reduce the programming

effort required thereby making the OpenGL Slide

Framework more accessible to non-programmers

(e.g. Maya (Autodesk, 2008) users, etc.)

ACKNOWLEDGEMENTS

We acknowledge the reviewers of this work and their

constructive feedback. This work was sponsored in

part by the Faculty of Engineering and Computer Sci-

ence (ENCS), Concordia University, Montreal, Que-

bec, Canada. We also thank Drs. Peter Grogono and

Sudhir Mudur.

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