Last thing - as I promised yesterday, I'd like to discuss how are we going to implemented post-processing effects for FL10 like those I've implemented for FL11. Implementation is inside Scene::Render3DCompleted() method and I've put comments to describe what's going on there, but here is a high-level algorighm:
1. Process image rendered to texture to calculate scene luminance. Currently it's implemented as two-stage iterative process, first stage being reducing 2D texture to 1D texture with caclulated sums of 8x8 pixels area, and then iterative further reduction to 128 times a pass. Compute Shaders are inside HDR_CalculateLuminance.hlsl (first stage) and HDR_Reduce.hlsl (second stage). Algorithms are pretty straightforward - please refer to code for details. After the process is completed, exposure is being calculated using formula exposure = 1 - luminance - this value will be used in later stages for tone-mapping and so-called "bright pass" to create bloom texture.
2. Create bloom texture by performing bright-pass (substracting BRIGHT_THRESHOLD value - defined in HDR_Includes.hlsl) and tune-mapping - increasing/reducing texture brightness using luminance - this is part of HDR lighting effect. Note that bloom texture is always created non-multisampled regardless from MSAA settings - with linear samples interpolation for MSAA modes.
3. Next step is downsampling bloom texture by factor of 2. It's a very simple algorighm that averages 2x2 pixel in original texture and writes result to output texture. See HDR_Downsample.hlsl.
4. After that we perform Gaussian blur. After some trial-and-error, I've settled down on 17-tap gaussian blur filter with standard deviation of 4. I calculated weights using MS Excel file published here:
http://theinstructionlimit.com/gaussian-blur-revisited-part-two (I've uploaded this Excel file to SC). This is a two-pass process consisting of horizontal and vertical passes. Again, algorithm is pretty simple - see HDR_GaussianBlur.hlsl
5. Then we upsample bloom texture back to original size. Here after some trial-and-error I came up with my own algorithm, see HDR_Upsample.hlsl for details. Kernel weights were calculated using Excel file upscale-filter.xlsx - I "invented" up with it myself
6. Next thing is combining bloom texture with original texture and tone-mapping original image. This is very simple shader, see HDR_CopyTextureWithExposure.hlsl.
7. Rendering a fullscreen quad onto backbuffer to display resulted image - this is the ONLY stage that is performed using regular pipeline - all of the rest is implemented in Compute Shaders.
So now I'd like to hear some ideas regarding how this can be implemented on FL10-level hardware
Thanks in advance for any ideas!
---------- Post added at 22:02 ---------- Previous post was at 21:55 ----------
Forgive me if I'm being thick, but I can't seem to find a way to download a complete archive...
No worries - I had the same problem first time I tried to get it
So here is how to get it:
1. Go to
https://bitbucket.org/asmi/ovp and choose "D3D11Client" branch by hovering "Branches" link on the left top part of the screen and selecting a branch from menu that opened up.
2. Hover "get source" link on the top right part of the screen and choose "zip". You'll get file with name like "asmi-ovp-e90912175309.zip".
3. Unpack archive somewhere - you'll get folder "asmi-ovp-e90912175309" (your actual folder name may be different, but it doesn't matter). Nagivate inside and copy everything you'll find inside to the Orbiter's root folder. IMPORTANT - you need Orbiter 2010 P2 111105 beta in order for the client to work - please refer to readme file for download link. I'd suggest you to create a copy of your current Orbiter's installation to avoid having to reinstall all of this should there be any problems.
Then read "D3D11CLIENT README.txt" file for further instructions. You may skip items 2 and 3 as you will be done with copying files at that point.
Let me know if you still have any questions or require additional assistance.
Please report here any issues you'll discover during running the client. Thank you!
