Cheat Engine

[thugorgibson]

I'm currently playing the original Just Cause on pc but, after seeing what the Xbox360 version has better than it, I decided to try and improve upon its look. The major issue I see in it is a shadow issue of some sort (maybe intended somehow): shadows are rendered much lighter on top of grass than on the roads. And at night time they completely vanish from any textures but the roads. This leads them to be almost unnoticeable, leaving the game world very bland and with low contrast.

While messing with Reshade and Special K, i've noticed the game renders shadows in the game world via a 1024x1024 "vertex buffer(?)" of some sort. Changing random values in Cheat Engine from "1024" to "2048" or "4096" was what eventually led me to this finding. When this "buffer"s width or height resolution gets changed, the shadows get completely misaligned from the world objects and move around with the camera perspective. I eventually stumbled upon the d3d9 tab on the top menu of Reshade, where this particular "buffer" shows up. Also, this "buffer" shows up in Special K under the "Live Render Target View" with a D24S8 format.

To the main question:
Would it be possible, either with Cheat Engine, a modified .dll or any other tool (e.g. Reshade), to use this "buffer"'s information to render new shadows in screen space atop the old ones or even replace them altogether?

Here's a link to an album with captioned images to better demonstrate my points, Just in Cause: imgur . com/a/rIirvl0
Thanks for reading!

[atom0s]

I'll use Direct3D 9 as an example, but I'm not sure what that game uses specifically. Vertex buffers are a block of memory allocated for the GPU to make use of that holds vertices to be drawn. The way they are drawn is then up to the developer if it's just going to be drawn with a texture applied to it or ran through any number of shaders/passes. Vertices will vary in size based on their definition.

They are drawn by a call that can be made to several of D3D9's APIs such as:
- DrawPrimitive
- DrawPrimitiveUP
- DrawIndexedPrimitive
- DrawIndexedPrimitiveUP

When these are called, you tell the rendering API what is contained in the buffer that is being used to draw at the time. The 'PrimitiveType' param tells the API which type of entries are within the buffer, and then the remaining arguments for each call tell the API how to use the buffer properly.

The more common types used would be:
- D3DPT_TRIANGLELIST
- D3DPT_TRIANGLESTRIP
- D3DPT_TRIANGLEFAN

That means that each primitive would be constructed of points that make up a triangle, and then 'x' number of triangles are contained within the buffer.

When you increase the buffer size without actually adding more data, you shift the expected number of triangles in the buffer, without having any there to be drawn. So the API will land up applying the data to the wrong areas in the game, or culling things altogether depending on where they should have been applied.

[thugorgibson]

Thanks for taking the time right such a detailed asnwer!
The game does happen to be using dx9, dunno if you took a look at the screens but the shadows appear to be laid out on said buffer and applied with a simple texture over the geometry. I thought going for a post processing route would be less taxing because my only gripe is with the shadows not being opaque enough - the thought ocurred to me that the info on the buffer could be intercepted and rendered on top of the final frame, maybe even with control on this new shadow's opacity through a Reshade like interface. Plus the game is compiled in such a way that accessing the mains files is impossible. Found a couple of ways to uncompress the arc files but only 4/5 can accessed, the main one, not being one of them. Would an approach like a d3d9 renderhook work ?
Thanks!

[atom0s]