Thetechbehinddx11unrealengine "Samaritan" demo

 

 

Link:

Http://www.nvidia.com/content/PDF/GDC2011/Epic.pdf

 

 

 

 

Deferred Shading

I mentioned it in an understatement that it is already popular in the industry. It is boring to publicize the epic, but I just want to update everyone's knodge DGE base. The Unreal Engine 3 is now defer.

 

 

 

Short hair

 

Use the camera aligned triangle strip and attach it with a texture, which is similar to grass rendering.

The focus is on the processing of alias. In the case of pure 1x buffer, high quality cannot be achieved:

Alpha test: Role

Alpha Blend: sort, fogging, DOF

Alpha to coverage: Problems with your Layers

The final choice is to make alphatest on 4 xmsaa buffer, and then resolve, which can be said to be super sample anti alias

 

 

Per fragment AA

Msaa has a white edge on the left, because the depth distance at the edge is different, but there must be a value.

Unreal marks this part using stencel, and then performs perpixel shading first. In this process, the stencel is completely written and can be ignored. The half-written part is where the white edge may exist, just do the perfragment shading again.

It is indeed a good solution.

 

 

Subsurface Scattering

The effect is great. It takes a lot of time to read the papers involved. Martin in the PDF is also a faint sentence. screenspace collects lighting contribution and randomly collects 16 samples.

 

 

 

 

Reflection

 

Use billboard + raytrace.

Plane reflection, that is, turning camera over the reflective surface. Then, the render scenario can only be used for water or simply flat the ground, but not for complex shapes.

The unreal method is very suitable for night situations. It only reflects some bright things and makes these things into a billboard for reflection.

Raytrace is used to sample the reflected content. Because it is a billboard, the calculation is relatively lightweight.

 

For a variety of strange reflections, The blurry algorithm can be used to change reflection ray slightly.

 

Reflection shadow, epic is really tangled,

Static is a distance field generated with an offline that exists in volume texture.

Dynamic uses the traditional planar Reflection Method to draw Depth Using Reflection camera, and draw quad based on each Texel of depth to generate final mask.

Final mask and billboard work together to create shadow reflection.

The consumption here is a bit amazing.

 

 

 

Bokeh

 

It is estimated that this is one of the most popular things after the GDC session, with sequins in the background.

 

The basic algorithm is brightpass detection. Draw quad or similar shapes on bright pixel.

The DOF solution of epic also includes the foreground and foreground blur. Therefore, three layers are used to distinguish them to avoid artifact.

 

Since this effect does not require accurate results, the low resolution solution must be used.

 

 

Others,

The energy preserving mentioned in this Article is to correct the illumination model to ensure that radiance and irradiance are consistent in energy... Is the player's Fire Wheel eye capable of recognizing this?

 

There are a lot of references in screen space subsurface scattering, so you need to take a look at them. But this is a little far away from the work at hand, so the priority is reduced.

 

 

 

In fact, there are not many special technologies in this demo, but it is shocking to take it out.

I once again explained that the development of the game has never been able to run on a single leg. Tech, art, and design are the best players in the game industry.

The era of Carmack, which relies solely on technology and individual capabilities, has passed.

 

The reflection part is my favorite, which is really good.