Windows WGL declarations for OpenGL rendering-context creation, destruction, procedure lookup, and current-context binding.

Imported functions

Stack effects list a C function's parameters with the first parameter on top; see the stack-order rule.

wglCreateContext

(Arg1 -- result) Creates an OpenGL rendering context for a device context.

Inputs

  • Arg1: HDC device-context handle whose pixel format is already set with SetPixelFormat.

Outputs

  • result: HGLRC rendering-context handle, or NIL on failure.

wglDeleteContext

(Arg1 -- result) Deletes an OpenGL rendering context.

Inputs

  • Arg1: HGLRC rendering-context handle to delete.

Outputs

  • result: Int32 nonzero on success, 0 on failure.

wglGetProcAddress

(procedureName -- result) Retrieves an extension procedure address for the current OpenGL rendering context.

Inputs

  • procedureName: Natx address of a zero-terminated byte string naming the procedure.

Outputs

  • result: Natx raw procedure address, or 0nx if no rendering context is current or lookup fails; to call the procedure, view the address as Code with addressToReference and a codeRef signature.

wglMakeCurrent

(arg2 arg1 -- result) Makes a rendering context current for a device context.

Inputs

  • arg2: HGLRC rendering-context handle, or a NIL HGLRC to release the calling thread's current context.
  • arg1: HDC device-context handle, ignored when arg2 is NIL.

Outputs

  • result: Int32 nonzero on success, 0 on failure.

Signature examples

Printing imported names during compilation shows the exact imported signatures.

"control"          use
"windows/opengl32" use

{} Int32 {} [
  @wglCreateContext printStack _:;
  @wglDeleteContext printStack _:;
  @wglGetProcAddress printStack _:;
  @wglMakeCurrent printStack _:;
  0
] "main" exportFunction

Expected Output During Compilation

{Arg1: {DC: (); unused: Int32;} Cref;} {GLRC: (); unused: Int32;} Cref {convention: "";} codeRef
{Arg1: {GLRC: (); unused: Int32;} Cref;} Int32 {convention: "";} codeRef
{lpParameter: Natx;} Natx {convention: "";} codeRef
{arg1: {DC: (); unused: Int32;} Cref; arg2: {GLRC: (); unused: Int32;} Cref;} Int32 {convention: "";} codeRef

wglGetProcAddress prints its input as lpParameter, the input name of an earlier kernel32 signature of the same schema (see codeRef on input names).

See also