CIS 566 Project 7: Deferred Renderer

Name: Linshen Xiao
PennKey: Linshen
Tested on: Windows 10, Intel(R) Core(TM) i7-6700HQ CPU @ 2.60GHz, 16.0GB, NVIDIA GeForce GTX 970M (Personal computer)

Demo

Goal: Learn an advanced rendering technique using the OpenGL pipeline and apply it to make artistic procedural post-processing effects.

Here is an overview of how the provided code renders its final output:

Each tick(), the provided OpenGLRenderer will perform the following operations:

renderToGBuffer: Render the 3D scene (wahoo.obj) into its G-Buffers using standard-vert.glsl and standard-frag.glsl.
renderFromGBuffer: Render the data in its G-Buffers into the first element of its post32Buffers array, which stores 32-bit colors rather than 8-bit colors so that the scene can be represented using high dynamic range values.
renderPostProcessHDR: Iterate over the collection of PostProcesses stored in OpenGLRenderer's post32Passes and apply each one, in sequence, to the image produced in the most recent render pass.
renderPostProcessLDR: Any LDR post-process effects will be applied in sequence just like the HDR processes.

I pass the following scene data out from standard-frag.glsl:

I use the 32-bit gbTexture to store both your surface normal and depth value; set its RGB to the surface normal's XYZ and its W to the depth value.

depth	albedo	normal

In deferred-render.glsl, I take the G-Buffer data that I output from the standard shader and implement:

Lambertian surface reflection and fake Blinn-Phong.
Ambient lighting, so areas that would be very dark are slightly lit.
Directional illumination.
An interesting procedural backdrop for your model. I add a sky and clout background from here. I use the depth that stored in the G-Buffer to decide whether or not a pixel is overlapped by a mesh.

In tonemap-frag.glsl, I implement one of the tone mapping algorithms listed on the Filmic Worlds blog which is Uncharted2Tonemap.

Original	tonemapping

I implement four of the effects.

Bloom: As a 32-bit HDR effect, I find and isolate areas of the image with a value higher than some parameter, then apply a blur effect and add that to the original image to apply a bloom effect. I got lots of information from here. I implement Gaussian blur method used from here. I modify the provided rendering pipeline as bloom requires storing frame data in two frame buffers at the same time.

Original	Bloom

Approximated depth of field: I choose a "focal length" for the virtual camera and compare the camera-space Z coordinate of the fragments to that distance. The farther the Z coordinate is from that length, the stronger a blur effect I apply to that fragment. I used the Gaussian blur metioned above.

Original	DOF

Artistic effect: I Implement a oil painting shader with kuwahara filter from here.

Original	Kuwahara

Rain effect::__ I Implement a rain drops effect shader modified from here. I also use a vignette effect shader so that the center of the screen won't be covered with rain drops.

Original	Rain