feat: implement custom W2S and refactor skeleton ESP to fix line stretching

[matveyel]

Hi everyone! This is my first pull request to YimMenu, so I apologize in advance if I missed any code style conventions or formatting rules. I'm open to any feedback!

🐛 The Problem

While using the Skeleton ESP, I noticed a severe visual bug: whenever a part of a ped's skeleton goes out of the field of view (FOV), the ESP lines stretch across the entire screen towards the top-left corner.
After some debugging, I found that the native GET_SCREEN_COORD_FROM_WORLD_COORD does not calculate actual off-screen coordinates. Instead, it forcefully returns (-1, -1) (or similar fallback values) when a point is outside the FOV. Because of this, the drawing logic connects the visible bone to these fallback coordinates, causing the massive line stretching.

🛠️ The Solution

To fix this, I reverse-engineered the native function to see how it calculates projections under the hood. I recreated the mechanics by directly reading the engine's matrices, completely bypassing the native's fallback behavior.

Changes made:

1. Added a pattern scan to retrieve the CViewport pointer.
2. Implemented a custom WorldToScreenPoint function that manually multiplies the View and Projection matrices. It calculates screen coordinates only if the point is in front of the camera (clipW > 0). If the point is behind the camera, it aborts the calculation and returns fallback coordinates (0.0f, 0.0f) alongside a false boolean.
3. Refactored the DrawSkeleton function to utilize this boolean return value. It now safely evaluates both joints (via a lambda) and only adds a line to the draw list if both points are strictly in front of the camera, which completely eliminates the stretching bug.

❓ Note on Architecture

Since I am new to the codebase, I wasn't entirely sure where the best place to put the WorldToScreenPoint function would be. For now, I placed it directly in esp.cpp.
If there is a better place for it (e.g., a math/utility class or a specific rendering header), please let me know, and I will gladly move it!

[tuyilmaz]

GET_SCREEN_COORD_FROM_WORLD_COORD returns false if the coordinates given are not visible to the rendering camera.

See https://alloc8or.re/gta5/nativedb/enhanced/?n=0x34E82F05DF2974F5

[matveyel]

GET_SCREEN_COORD_FROM_WORLD_COORD returns false if the coordinates given are not visible to the rendering camera.

See https://alloc8or.re/gta5/nativedb/enhanced/?n=0x34E82F05DF2974F5

Yes, but it's limited by the player's field of view, which makes it difficult to draw a skeleton bone if one of its points is outside the field of view but remains in front of the camera plane.
Of course, you could avoid drawing the bone altogether if at least one point is outside the field of view. But it's not cool.
I proposed a solution that allows you to draw the skeleton even if one of its points is outside the field of view but still remains in front of the camera plane (which allows for correct calculation of screen coordinates).
Plus, thanks to this, it is no longer necessary to call the native game function, since we can directly read the camera matrix data and calculate the on-screen position of objects.