Source Apex Legends Proper FOV Projection & View Render Offsets

[byte_corvus]

Found a clean way to handle FOV projection for Apex by grabbing the precomputed cot(fov/2) value directly from view render. Works nicely and saves you from doing redundant math every frame. Enjoy, pasters.

Simple angle delta:

float c_vector_3f::calc_fov( const c_vector_3f& o ) const
{
    return math::rad_to_deg( std::acosf( std::cosf( math::deg_to_rad( o.x - x ) ) 
        * std::cosf( math::deg_to_rad( o.y - y ) ) ) );
}

And the magic:

float engine::project_fov( float fov_deg )
{
    ImGuiIO& io = ImGui::GetIO( );
    float half_w = io.DisplaySize.x * 0.5f;
    float cot_half_fov = driver::read< float >( 
        reinterpret_cast< uintptr_t >( get_view_render( ) ) + 0xD0 );
    return half_w * std::tanf( math::deg_to_rad( fov_deg ) ) / cot_half_fov;
}

Spoiler: Technical Breakdown

The 0xD0 offset in view render gives us the cotangent, which simplifies the projection math significantly. If you're using a custom external engine, make sure your view_render pointer is validated before reading, otherwise you'll hit a null dereference during the loop.

Has anyone integrated this into their aimbot prediction yet? Curious if this helps with micro-stuttering on high-fov settings. Drop your results below.