bgfx_init() second parameter needs to be casted

[malobre]

Environment

• LWJGL version: 3.1.5
• LWJGL build #: 1
• Java version: 9 (I'm programming in Kotlin 1.2.20)
• Platform: Windows
• Module: BGFX

Description

/** PCI */
public static final short
    BGFX_PCI_ID_NONE                = 0x0,
    BGFX_PCI_ID_SOFTWARE_RASTERIZER = 0x1,
    BGFX_PCI_ID_AMD                 = 0x1002,
    BGFX_PCI_ID_INTEL               = (short)0x8086,
    BGFX_PCI_ID_NVIDIA              = 0x10DE;

/**
 * Initializes bgfx library.
 *
 * @param _type      select rendering backend. When set to {@link #BGFX_RENDERER_TYPE_COUNT RENDERER_TYPE_COUNT}, default rendering backend will be selected. One of:<br><table><tr><td>{@link #BGFX_RENDERER_TYPE_NOOP RENDERER_TYPE_NOOP}</td><td>{@link #BGFX_RENDERER_TYPE_DIRECT3D9 RENDERER_TYPE_DIRECT3D9}</td><td>{@link #BGFX_RENDERER_TYPE_DIRECT3D11 RENDERER_TYPE_DIRECT3D11}</td></tr><tr><td>{@link #BGFX_RENDERER_TYPE_DIRECT3D12 RENDERER_TYPE_DIRECT3D12}</td><td>{@link #BGFX_RENDERER_TYPE_GNM RENDERER_TYPE_GNM}</td><td>{@link #BGFX_RENDERER_TYPE_METAL RENDERER_TYPE_METAL}</td></tr><tr><td>{@link #BGFX_RENDERER_TYPE_OPENGLES RENDERER_TYPE_OPENGLES}</td><td>{@link #BGFX_RENDERER_TYPE_OPENGL RENDERER_TYPE_OPENGL}</td><td>{@link #BGFX_RENDERER_TYPE_VULKAN RENDERER_TYPE_VULKAN}</td></tr><tr><td>{@link #BGFX_RENDERER_TYPE_COUNT RENDERER_TYPE_COUNT}</td></tr></table>
 * @param _vendorId  vendor PCI id. If set to {@link #BGFX_PCI_ID_NONE PCI_ID_NONE} it will select the first device.
 * @param _deviceId  device id. If set to 0 it will select first device, or device with matching id.
 * @param _callback  provide application specific callback interface
 * @param _allocator custom allocator. When custom allocator is not specified, library uses default CRT allocator. The library assumes custom allocator is thread safe.
 * 
 * @return `true` if initialization was successful
 */
@NativeType("bool")
public static boolean bgfx_init(@NativeType("bgfx_renderer_type_t") int _type, @NativeType("uint16_t") int _vendorId, @NativeType("uint16_t") int _deviceId, @NativeType("bgfx_callback_interface_t *") BGFXCallbackInterface _callback, @NativeType("bgfx_allocator_interface_t *") BGFXAllocatorInterface _allocator) {
    return nbgfx_init(_type, (short)_vendorId, (short)_deviceId, memAddressSafe(_callback), memAddressSafe(_allocator));
}

Second parameter of bgfx_init(), vendorId cannot be set to BGFX_PCI_ID_NONE or BGFX_PCI_ID_* without casting the constant to an Int.

[malobre]

Seems to be the same with bgfx_set_view_clear() and its second parameter, short constants needs to be casted to ints

[Spasi]

Indeed, there is no reason to map _vendorId to an int. The same applies to the _side parameter of bgfx_update_texture_cube.

The situation with bgfx_set_view_clear and other functions with bitfield parameters (e.g. buffer creation flags) is more complicated. As soon as you need to || two or more flags together, mapping the parameter to a short becomes painful. In both Java and Kotlin. For example in Kotlin you'd need to do:

(BGFX_CLEAR_COLOR.toInt() or BGFX_CLEAR_DEPTH.toInt()).toShort()

There is an or that works on Short in kotlin.experimental, but it would still be painful in Java (and Java usability takes priority over Kotlin).

May I suggest a simple extension property:

val Short.i get() = this.toInt()

Then you can do:

BGFX_CLEAR_COLOR.i or BGFX_CLEAR_DEPTH.i // or
(BGFX_CLEAR_COLOR or BGFX_CLEAR_DEPTH).i // with kotlin.experimental.or

[malobre]

I'm currently using toInt() but isn't it possible to just declare the constants that are used in bitfield parameters as Ints insteads of Shorts ? Or am I missing something ?

[Spasi]

@malobre Thanks!

If you have more suggestions, please post in this issue.