Graphic Rendering

Tasks 1

If Clipping was not in the Pipeline

If the clipping step was not in the graphics pipeline then all objects or part of objects that are not visible will still be processed, thus slowing down future processes and wasting processing time and power.

What are OpenGL and Direct3D and what is their purpose?

OpenGL and Direct3D are both API’s, this stands for Application Programming Interface. An API calculates a series of mathematical functions which can be understood by hardware such as graphics cards.

The reason we use API’s are because they allow 3D software application and or games to process the 3D model data (determining position of models, lighting and texturing) at a much faster speed.

OpenGL and Direct3D are used by programmers to process games created on 3D software engines like Unity and 3DS Max before they are again analysed by a graphics card, in an Xbox 360 for example.

Vertex Information

The API’s such as OpenGL and Direct3D calculate where 3D models are in a 3D world and will process how they will then be illuminated.

Vertices are used to connect and create faces, these faces are then processed to which the light that falls on the face will be determined. After the polygons have had their texture coordinates stored, a shader will then be applied to the vertices.

X = 0, Y = 0, Z = 0

Graphic Rendering

Tasks 2

Simple Scene

Here’s my simple scene that I made to test out the Radiosity and Ray Tracing render functions…

Radiosity

This is how my render turned out after using Radiosity on the 3D scene…

It is extremely bright, to the point that the only visible shadows are on the chair closest to the screen.

Ray Tracing

This is how my render turned out after using Ray Tracing on my textures and the rendering the …

Unlike when I used Radiosity, this one is much darker and the textures reflect the 3D models quite well…

Radiosity in Battlefield 3

After doing some searching on what of the latest 3D games use the previously mentioned lighting techniques and I came upon BF3.

EA Digital Illusion CE (DICE for short) really liked Radiosity after seeing how well it worked in their ‘Mirror’s Edge’ game, however they believe it took to long to develop and so partnered with Enlighten (a real-time radiosity pioneer) to provide a lightning-fast workflow for the lighting artists.

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Bump MapBump Mapping gives you the illusion of depth by controlling the way light in a scene is reflected on objects thus simulating detail on objects by artificially rendering light rays, to how they would look if the geometric deformation actually existed.

On the next page I am going to show how I have used bump mapping using this simple model below…

This model was created using three types of primitives; a sphere, three boxes and three torus.

Bump MapTo bump map, first I had to create a texture, making sure there was a clear contrast between light and dark colours I used black and white, most people would use black and white however you can also use grayscale.

After the texture was finished I placed it in the material editor in 3DS Max and went to the Maps drop down menu to which I ticked Bump and browsed for my texture.

This turned the sphere preview of my texture as you can see below…

Bump MapThe next step was to apply the bump to the simple model I created and this is my result…

The difference (besides the colour of the plain grey texture) being that now the bump map I made looks as though a pattern has been engraved onto the simple model.

Using this technique it is possible to make even low poly models appear to have a lot of high quality detail…

Vertex and Pixel Shading in Ninja

Gaiden 3Ninja Gaiden 3 is a game that I have been enjoying a lot lately and so I decided to use this as an example for vertex and pixel shading. In Ninja Gaiden 3 there are various models that make use of vertex shading, a few examples being:

Shinobi Shozoku (Ninja robes) – the ninja’s robes in Ninja Trials Mode crumple whilst running and around and fighting as well as slightly crumpling when the character breathes.

Vertex and Pixel Shading in Ninja

Gaiden 3When nearing the end of Day 3 on NG3, I was forced into a situation where I had to defeat a rampaging Tyrannosaurus Rex that had been modified.

In this battle I really noticed the use of vertex shader in both Ryu’s scarf (crumpling like the ninja robes) and the skin of the T-Rex was constantly stretching and tightening to accommodate the T-Rex’s movements.

Here’s a YouTube video showing the boss battle I am talking about…

http://www.youtube.com/watch?v=kQ7YAu6TwS0

Vertex and Pixel Shading in Ninja

Gaiden 3Pixel shading is extremely evident in the NG3 as the majority of models have been textured brilliantly, effectively using bump mapping and normal mapping to give life to the already high resolution models.

A perfect example of bump mapping that NG3 has used on a major character model would be the Regent of the Mask’s model…

(next page)

Vertex and Pixel Shading in Ninja

Gaiden 3After observing the textures on this model it becomes very clear that bump mapping has been masterfully applied here, integrated into the cloth material like the robe and belt as well as into the metal alloys such as the gauntlets and the sword which appears to have very intricate and engraved markings, thanks o bump mapping…

Regent of the Mask

Vertex and Pixel Shading in Ninja

Gaiden 3Pixel shading also allows for various visual effects that NG3 made sure to take advantage of such as blurring and blooming, an example being the blooming effect which slightly increases illumination in the background whilst losing focus however increasing focus on models in the foreground allowing them to stand out more without a contrasting background as a distraction…

Vertex and Pixel Shading in Ninja

Gaiden 3

Vertex and Pixel Shading in Ninja

Gaiden 3Pixel shading also allows for various visual effects that NG3 made sure to take advantage of such as blurring and blooming, an example being the blooming effect which slightly increases illumination in the background whilst losing focus however increasing focus on models in the foreground allowing them to stand out more without a contrasting background as a distraction…