Crysis 2 DirectX 11 Ultra Upgrade Effects Comparison - Page Two
Realistic Shadows With Variable Penumbra
In addition to the soft shadowing seen in the Parallax Occlusion Mapping example, Crytek has implemented Variable Penumbra Soft Shadows. Replicating reality, a Penumbra shadow becomes softer as the distance between the end point of the shadow and the shadow’s source increases, rather than remaining uniformly blurred.
In the animated comparison the shadows, be they from the tree, the stretcher, or the ambulance, are identical when DirectX 11 Penumbra is disabled. The look and density is identical, and the darkness uniform, regardless of other elements in the scene. Enabled, the tree’s shadow is blurrier due to the distance over which it is cast, and the shadows of the ambulance, stretcher and big rig are sharper due to their proximity to the end point, dictated by the angle of the sun and their positions in the scene. In other words, all shadows in the scene no longer look exactly the same, adding depth and immersion to the environment.
Full Resolution High Dynamic Range Motion Blur
The Ultra Upgrade sees the return of full resolution temporal anti-aliasing, commonly referred to as motion blur. The new, improved and more efficient DirectX 11 version provides sharper motion blur compared to its DirectX 9 counterpart, resulting in higher overall image definition and the removal of blur bleeding on the character’s weapon and hands, as shown in the example below.
Particle Motion Blur & Shadowing
Thanks to the reintroduction of the aforementioned temporal anti-aliasing, particles can be accurately blurred also, meaning the faster they move the more they will blur, an example of which can be seen in the fires in the very first level of the game. Furthermore, particles can be shadowed, as seen in the example below, improving lighting consistency and enhancing realism. And as a final upgrade, Crytek’s visual effects artists have gone back through the game and enhanced each set of particles wherever possible.
Sprite-Based Bokeh Depth Of Field
Like Sub-Surface Scattering, Sprite-Based Bokeh Depth Of Field is another big upgrade that will become more and more prevalent in upcoming games. Based on the out-of-focus depth of field effects used by filmmakers to add cinematic flair to their productions, Crytek’s DirectX 11 implementation replaces the DirectX 9 post-processing technique with a sprite-based rendering pass, allowing artists to dictate the shape and size of the Bokeh sprites, resulting in the circular or pentagonal blurred shapes shown in the in-game animated example below.
A real-world example of the Bokeh depth of field effect - Image Source
Due to the limitations of DirectX 9 Crytek was previously forced to limit the number of out-of-focus areas in a scene to minimize undesirable under-sampling, the process by which a screen element is rendered below the screen’s native resolution and then stretched to correctly fit. The end result is a lower quality image that may appear blocky or aliased as the information contained within one pixel is being spanned across multiple pixels simultaneously. Enlarging a low resolution image on a large monitor shows a similar effect.
Despite the change to the sprite-based bokeh technique there is still room for improvement, as Crytek explains: “Unfortunately, graphics hardware is still a few years away from being able to efficiently use such techniques at full screen resolutions. Thus, this implementation is done at half resolution and includes a number of additional optimizations.” Despite these technological limitations the DirectX 11 implementation is far superior, blurring the entire scene and applying additional bokeh effects wherever defined, without any under-sampling.
Screen Space Directional Occlusion & Contact Shadows
Screen Space Ambient Occlusion was a significant step up from standard lighting when it was first introduced in the original Crysis, and now they’re introducing an upgrade called Screen Space Directional Occlusion.
SSAO gave scenes a greater sense of depth by rendering shadows and color accurately based on the depth of the image and the ambient light sources available. SSAO achieved this by taking a sample pixel, calculating how close it is to a random number of the neighboring pixels and then darkening it based on that number, the idea being that the closer pixels and objects are to one another the less light is being bounced between them and the available light sources. In practice the effect didn’t always work as hoped, suffered from banding and artifacting and was particularly taxing on the GPU, though when it did work it could greatly add to a scene, darkening creases, holes and surfaces that are close to each other.
Unfortunately, SSAO ignored all information regarding the directionality of incoming light, which is where Screen Space Directional Occlusion enters the picture. Screen Space Directional Occlusion requires very little extra in the way of processing power and creates superior results by accounting for the direction of incoming light and being able to bounce light sources once for greater realism, which can be seen most prominently in the in-game example below as smooth contact shadows cast realistically around the rubble and sand bags. Interior, enclosed scenes, such as office environments, are further enhanced by improved self-shadowing and dramatically improved global lighting, and as an added benefit SSDO can bounce colored lighting, an effect that is at times noticeable in outdoor environments.
The top row shows the difference between no Screen Space Ambient Occlusion, Screen Space Ambient Occlusion, Screen Space Directional Occlusion and Screen Space Directional Occlusion with one additional lighting bounce. The insets in the bottom row show the differences in detail. With Ambient Occlusion shadows are completely grey, whereas with Directional Occlusion red and blue shadows are visible. The images on the bottom right show the optional indirect lighting bounce. Note the yellow light, bouncing from the box to the ground in the right-most image.
Realtime Local Reflections
Real-time, accurate reflections are one of the most demanding effects in modern-day game engines. In past versions of Crytek’s CryEngine, the options have been limited to planar reflections, as used for water, and cube maps, an extremely old technique that is only capable of producing low-resolution, poorly defined reflections that can’t be recursively reflected.
For the DirectX 11 Ultra Upgrade Crytek has implemented Realtime Local Reflections, which approximate ray-traced High Dynamic Range reflections, the technique used by Pixar and co. to ensure absolute accuracy when rendering their animated movie scenes. The approximated Realtime Local Reflections are able to self-reflect and reflect images from other surfaces also, and are of course fast enough to be rendered in real-time on modern-day technology (ray-traced reflections render at only a few frames per second on the most powerful of systems).
This upgrade is best demonstrated by the first example below, in which the soldier and his surroundings are reflected in the panel propped up against the wall, and the glossy floor. In the second example the entire scene is reflected to a high degree of accuracy.
High Resolution Textures
Weighing in at 1.7GB, the texture pack increases the resolution of Crysis 2’s assets by a factor of two, quadrupling the game’s memory requirements in the process. As such, players will require a 64-bit operating system and a graphics card with 1GB of memory just to enable them.
The difference is dramatic with the pack installed and enabled, massively improving the appearance of roads, cobbles, and just about every object and surface in the entire game. Combined with tessellation, Parallax Occlusion Mapping and the other effects, Crysis 2 instantly becomes the benchmark for game graphics on the PC. And as an added bonus, all modders will be able to use the new textures in their projects.
Crytek took flak from gamers for not having created a PC-centric version of Crysis 2 at launch, but with the DirectX 11 Ultra Upgrade, these concerns are finally put to rest. As is clear to see from the images, the Crysis 2 DirectX 11 Ultra Upgrade lives up to its name. The combined use of tessellation and Parallax Occlusion Mapping improves detail levels in virtually every setting of the game. The enhancements to water, shadows, motion blur, though subtle when viewed as isolated screenshots, add substantially to the visual polish when experienced in unison in-game. Perhaps most importantly, with this upgrade, Crytek has reaffirmed its commitment to PC gamers and reasserted the graphical preeminence of the Crysis franchise.