gui/gui-lib/mred/private/wx/gtk/gl-context.rkt
2015-10-18 18:08:05 -06:00

486 lines
18 KiB
Racket

#lang racket/base
(require racket/class
racket/promise
racket/string
ffi/unsafe
ffi/unsafe/define
ffi/unsafe/alloc
ffi/cvector
(prefix-in draw: racket/draw/private/gl-context)
racket/draw/private/gl-config
"../../lock.rkt"
"types.rkt"
"utils.rkt"
"window.rkt"
"x11.rkt")
(provide
(protect-out prepare-widget-gl-context
create-widget-gl-context
create-and-install-gl-context
get-gdk-pixmap
install-gl-context))
(define (ffi-lib/complaint-on-failure name vers)
(ffi-lib name vers
#:fail (lambda ()
(log-warning "could not load library ~a ~a"
name vers)
#f)))
;; ===================================================================================================
;; X11/GLX FFI
(define gl-lib (ffi-lib/complaint-on-failure "libGL" '("1" "")))
(define-ffi-definer define-glx gl-lib
#:default-make-fail make-not-available)
;; X #defines/typedefs/enums
(define _Display (_cpointer 'Display))
(define _XErrorEvent (_cpointer 'XErrorEvent))
(define _XID _ulong)
(define True 1)
(define False 0)
(define None 0)
(define Success 0)
;; GLX #defines/typedefs/enums
(define _GLXFBConfig (_cpointer 'GLXFBConfig))
(define _GLXContext (_cpointer/null 'GLXContext))
(define _XVisualInfo (_cpointer 'XVisualInfo))
;; Attribute tokens for glXGetConfig variants (all GLX versions):
(define GLX_DOUBLEBUFFER 5)
(define GLX_STEREO 6)
(define GLX_DEPTH_SIZE 12)
(define GLX_STENCIL_SIZE 13)
(define GLX_ACCUM_RED_SIZE 14)
(define GLX_ACCUM_GREEN_SIZE 15)
(define GLX_ACCUM_BLUE_SIZE 16)
(define GLX_ACCUM_ALPHA_SIZE 17)
;; GLX 1.3 and later:
(define GLX_X_RENDERABLE #x8012)
(define GLX_RGBA_TYPE #x8014)
;; GLX 1.4 and later:
(define GLX_SAMPLES #x186a1)
(define GLX_SAMPLE_BUFFERS #x186a0)
;; Attribute tokens for glXCreateContextAttribsARB (also GLX 1.4 and later):
(define GLX_CONTEXT_MAJOR_VERSION_ARB #x2091)
(define GLX_CONTEXT_MINOR_VERSION_ARB #x2092)
(define GLX_CONTEXT_FLAGS_ARB #x2094)
(define GLX_CONTEXT_PROFILE_MASK_ARB #x9126)
;; GLX_CONTEXT_FLAGS_ARB bits
(define GLX_CONTEXT_DEBUG_BIT_ARB #x1)
(define GLX_CONTEXT_FORWARD_COMPATIBLE_BIT_ARB #x2)
;; GLX_CONTEXT_PROFILE_MASK_ARB bits
(define GLX_CONTEXT_CORE_PROFILE_BIT_ARB #x1)
(define GLX_CONTEXT_COMPATIBILITY_PROFILE_BIT_ARB #x2)
(define-x11 XFree (_fun _pointer -> _int)
#:wrap (deallocator))
(define-x11 XSetErrorHandler
(_fun _fpointer -> _fpointer))
(define-x11 XSync
(_fun _Display _int -> _void))
(define-glx glXQueryVersion
(_fun _Display (major : (_ptr o _int)) (minor : (_ptr o _int))
-> (ret : _bool)
-> (values ret major minor)))
(define-glx glXQueryExtensionsString
(_fun _Display _int -> _string/utf-8))
(define-glx glXChooseFBConfig
(_fun _Display _int (_list i _int) (len : (_ptr o _int))
-> (_cvector o _GLXFBConfig len))
#:wrap (allocator (λ (v) (XFree (cvector-ptr v)))))
(define-glx glXGetFBConfigAttrib
(_fun _Display _GLXFBConfig _int (out : (_ptr o _int))
-> (ret : _int)
-> (values ret out)))
(define-glx glXCreateNewContext
(_fun _Display _GLXFBConfig _int _GLXContext _bool -> _GLXContext))
(define-glx glXDestroyContext
(_fun _Display _GLXContext -> _void))
(define-glx glXMakeCurrent
(_fun _Display _XID _GLXContext -> _bool))
(define-glx glXSwapBuffers
(_fun _Display _XID -> _void))
(define-glx glXIsDirect
(_fun _Display _GLXContext -> _bool))
(define-glx glXGetVisualFromFBConfig
(_fun _Display _GLXFBConfig -> _XVisualInfo)
#:wrap (allocator XFree))
(define-glx glXCreateGLXPixmap
(_fun _Display _XVisualInfo _XID -> _XID))
(define-glx glXDestroyGLXPixmap
(_fun _Display _XID -> _void))
(define-glx glXGetProcAddressARB
(_fun _string -> _pointer))
(define lazy-glXCreateContextAttribsARB
(delay
(function-ptr (glXGetProcAddressARB "glXCreateContextAttribsARB")
(_fun _Display _GLXFBConfig _GLXContext _bool (_list i _int)
-> _GLXContext))))
(define (glXCreateContextAttribsARB . args)
(apply (force lazy-glXCreateContextAttribsARB) args))
(define-gtk gtk_widget_get_display (_fun _GtkWidget -> _GdkDisplay))
(define-gtk gtk_widget_get_screen (_fun _GtkWidget -> _GdkScreen))
(define-glx glXSwapIntervalEXT (_fun _Display _XID _int -> _void)
#:fail (lambda () void))
;; ===================================================================================================
;; GLX versions and extensions queries
(define lazy-get-glx-version
(delay
(define-values (worked? glx-major glx-minor)
(glXQueryVersion (gdk_x11_display_get_xdisplay (gdk_display_get_default))))
(unless worked?
(error 'get-glx-version "can't get GLX version using default display"))
(define glx-version (+ glx-major (/ glx-minor 10)))
(when (< glx-version #e1.3)
(error 'get-glx-version "need GLX version 1.3 or greater; given version ~a.~a"
glx-major glx-minor))
glx-version))
;; -> positive-exact-rational
(define (get-glx-version)
(force lazy-get-glx-version))
(define lazy-glx-extensions
(delay
(define str
(glXQueryExtensionsString (gdk_x11_display_get_xdisplay (gdk_display_get_default))
(gdk_x11_screen_get_screen_number (gdk_screen_get_default))))
(string-split str)))
(define lazy-GLX_ARB_create_context?
(delay (member "GLX_ARB_create_context"
(force lazy-glx-extensions))))
(define lazy-GLX_ARB_create_context_profile?
(delay (member "GLX_ARB_create_context_profile"
(force lazy-glx-extensions))))
;; ===================================================================================================
;; Wrapper for the _GLXContext (if we can get one from GLX)
(define gl-context%
(class draw:gl-context%
(init-field gl display drawable pixmap)
(define/override (get-handle) gl)
(define/public (get-gtk-display) display)
(define/public (get-gtk-drawable) drawable)
(define/public (get-glx-pixmap) pixmap)
(define (get-drawable-xid)
(if pixmap pixmap (gdk_x11_drawable_get_xid drawable)))
(define/override (draw:do-call-as-current t)
(define xdisplay (gdk_x11_display_get_xdisplay display))
(dynamic-wind
(lambda ()
(glXMakeCurrent xdisplay (get-drawable-xid) gl))
t
(lambda ()
(glXMakeCurrent xdisplay 0 #f))))
(define/override (draw:do-swap-buffers)
(glXSwapBuffers (gdk_x11_display_get_xdisplay display)
(get-drawable-xid)))
(super-new)))
;; ===================================================================================================
;; Getting OpenGL contexts
;; STUPIDITY ALERT
;; Apparently, the designers of glXCreateNewContext and glXCreateContextAttribsARB didn't trust us to
;; check return values or output arguments, so when these functions fail, they raise an X error and
;; send an error code to the X error handler. X errors, by default, *terminate the program* and print
;; an annoyingly vague, barely helpful error message.
;; This is especially bad with glXCreateContextAttribsARB, which always fails (i.e. crashes the
;; program) if we ask for an unsupported OpenGL version. Worse, this is the only way to find out
;; which OpenGL versions are available!
;; So we override the X error handler to silently fail, and sync right after the calls to make sure
;; the errors are processed immediately. With glXCreateContextAttribsARB, we then try the next lowest
;; OpenGL version. If all attempts to get a context fail, we return #f.
(define create-context-error? #f)
(define (flag-x-error-handler xdisplay xerrorevent)
(set! create-context-error? #t)
0)
;; _Display _GLXFBConfig _GLXContext -> _GLXContext
(define (glx-create-new-context xdisplay cfg share-gl)
;; Sync right now, or the sync further on could crash Racket with an [xcb] error about events
;; happening out of sequence
(XSync xdisplay False)
(define old-handler #f)
(define gl
(dynamic-wind
(λ ()
(set! old-handler
(XSetErrorHandler (cast flag-x-error-handler
(_fun #:atomic? #t _Display _XErrorEvent -> _int)
_fpointer))))
(λ ()
(set! create-context-error? #f)
(glXCreateNewContext xdisplay cfg GLX_RGBA_TYPE share-gl #t))
(λ ()
;; Sync to ensure errors are processed
(XSync xdisplay False)
(XSetErrorHandler old-handler))))
(cond
[(and gl create-context-error?)
(log-error (string-append
"gl-context: glXCreateNewContext raised an error but (contrary to standards)"
" returned a non-NULL context; ignoring possibly corrupt context"))
#f]
[else
(unless gl
(log-warning "gl-context: glXCreateNewContext was unable to get an OpenGL context"))
gl]))
;; OpenGL core versions we'll try to get, in order
(define core-gl-versions '((4 5) (4 4) (4 3) (4 2) (4 1) (4 0) (3 3) (3 2) (3 1) (3 0)))
;; _Display _GLXFBConfig _GLXContext (List Byte Byte) -> _GLXContext
(define (glx-create-context-attribs xdisplay cfg share-gl gl-version)
;; Sync right now, or the sync further on could crash Racket with an [xcb] error about events
;; happening out of sequence
(XSync xdisplay False)
(define gl-major (car gl-version))
(define gl-minor (cadr gl-version))
(define context-attribs
(list GLX_CONTEXT_MAJOR_VERSION_ARB gl-major
GLX_CONTEXT_MINOR_VERSION_ARB gl-minor
GLX_CONTEXT_PROFILE_MASK_ARB GLX_CONTEXT_CORE_PROFILE_BIT_ARB
None))
(define old-handler #f)
(define gl
(dynamic-wind
(λ ()
(set! old-handler (XSetErrorHandler flag-x-error-handler)))
(λ ()
(set! create-context-error? #f)
(glXCreateContextAttribsARB xdisplay cfg share-gl #t context-attribs))
(λ ()
;; Sync to ensure errors are processed
(XSync xdisplay False)
(XSetErrorHandler old-handler))))
(cond
[(and gl create-context-error?)
(log-error (string-append
"gl-context: glXCreateContextAttribsARB raised an error for version ~a.~a but"
" (contrary to standards) returned a non-NULL context;"
" ignoring possibly corrupt context")
gl-major gl-minor)
#f]
[else
(unless gl
(log-info "gl-context: glXCreateContextAttribsARB returned NULL for version ~a.~a"
gl-major gl-minor))
gl]))
;; _Display _GLXFBConfig _GLXContext -> _GLXContext
(define (glx-create-core-context xdisplay cfg share-gl)
(let/ec return
(for ([gl-version (in-list core-gl-versions)])
(define gl (glx-create-context-attribs xdisplay cfg share-gl gl-version))
(when gl (return gl)))
(log-warning "gl-context: unable to get core context; falling back")
(glx-create-new-context xdisplay cfg share-gl)))
;; ===================================================================================================
;; (or/c #f _GtkWidget) -> _GdkDisplay
(define (gtk-maybe-widget-get-display widget)
(cond [widget (gtk_widget_get_display widget)]
[else (gdk_display_get_default)]))
;; (or/c #f _GtkWidget) -> _GdkScreen
(define (gtk-maybe-widget-get-screen widget)
(cond [widget (gtk_widget_get_screen widget)]
[else (gdk_screen_get_default)]))
;; _Display _GLXFBConfig int int -> int
(define (glx-get-fbconfig-attrib xdisplay cfg attrib bad-value)
(define-values (err value) (glXGetFBConfigAttrib xdisplay cfg attrib))
(if (= err Success) value bad-value))
;; (or/c #f _GtkWidget) _GdkDrawable gl-config% boolean? -> gl-context%
;; where _GdkDrawable = (or/c _GtkWindow _GdkPixmap)
(define (make-gtk-drawable-gl-context widget drawable conf wants-double?)
(define glx-version (get-glx-version))
;; If widget isn't #f, use its display and screen
(define display (gtk-maybe-widget-get-display widget))
(define screen (gtk-maybe-widget-get-screen widget))
;; Get the X objects wrapped by the GDK objects
(define xdisplay (gdk_x11_display_get_xdisplay display))
(define xscreen (gdk_x11_screen_get_screen_number screen))
;; Create an attribute list using the GL config
(define xattribs
(append
;; Be aware: we may get double buffering even if we don't ask for it
(if wants-double?
(if (send conf get-double-buffered) (list GLX_DOUBLEBUFFER True) null)
null)
(if (send conf get-stereo) (list GLX_STEREO True) null)
;; Finish out with standard GLX 1.3 attributes
(list
GLX_X_RENDERABLE True ; yes, we want to use OpenGL to render today
GLX_DEPTH_SIZE (send conf get-depth-size)
GLX_STENCIL_SIZE (send conf get-stencil-size)
GLX_ACCUM_RED_SIZE (send conf get-accum-size)
GLX_ACCUM_GREEN_SIZE (send conf get-accum-size)
GLX_ACCUM_BLUE_SIZE (send conf get-accum-size)
GLX_ACCUM_ALPHA_SIZE (send conf get-accum-size)
;; GLX_SAMPLES is handled below - GLX regards it as an absolute lower bound, which makes it
;; too easy for user programs to fail to get a context
None)))
(define multisample-size (send conf get-multisample-size))
;; Get all framebuffer configs for this display and screen that match the requested attributes,
;; then sort them to put the best in front
;; GLX already sorts them pretty well, so we just need a stable sort on multisamples at the moment
(define cfgs
(let* ([cfgs (cvector->list (glXChooseFBConfig xdisplay xscreen xattribs))]
;; Keep all configs with multisample size <= requested (i.e. make multisample-size an
;; abolute upper bound)
[cfgs (if (< glx-version #e1.4)
cfgs
(filter (λ (cfg)
(define m (glx-get-fbconfig-attrib xdisplay cfg GLX_SAMPLES 0))
(<= m multisample-size))
cfgs))]
;; Sort all configs by multisample size, decreasing
[cfgs (if (< glx-version #e1.4)
cfgs
(sort cfgs >
#:key (λ (cfg) (glx-get-fbconfig-attrib xdisplay cfg GLX_SAMPLES 0))
#:cache-keys? #t))])
cfgs))
(cond
[(null? cfgs) #f]
[else
;; The framebuffer configs are sorted best-first, so choose the first
(define cfg (car cfgs))
(define share-gl
(let ([share-ctxt (send conf get-share-context)])
(and share-ctxt (send share-ctxt get-handle))))
;; Get a GL context
(define gl
(if (and (>= glx-version #e1.4)
(not (send conf get-legacy?))
(force lazy-GLX_ARB_create_context?)
(force lazy-GLX_ARB_create_context_profile?))
;; If the GLX version is high enough, legacy? is #f, and GLX has the right extensions,
;; try to get a core-profile context
(glx-create-core-context xdisplay cfg share-gl)
;; Otherwise use the old method
(glx-create-new-context xdisplay cfg share-gl)))
;; The above will return a direct rendering context when it can
;; If it doesn't, the context will be version 1.4 or lower, unless GLX is implemented with
;; proprietary extensions (NVIDIA's drivers sometimes do this)
(when (and widget (send conf get-sync-swap))
(glXSwapIntervalEXT xdisplay (gdk_x11_drawable_get_xid drawable) 1))
;; Now wrap the GLX context in a gl-context%
(cond
[gl
;; If there's no widget, this is for a pixmap, so get the stupid GLX wrapper for it or
;; indirect rendering may crash on some systems (notably mine)
(define pixmap
(if widget #f (glXCreateGLXPixmap xdisplay
(glXGetVisualFromFBConfig xdisplay cfg)
(if gtk3?
(cast drawable _Pixmap _ulong)
(gdk_x11_drawable_get_xid drawable)))))
(define ctxt (new gl-context% [gl gl] [display display] [drawable drawable] [pixmap pixmap]))
;; Refcount these so they don't go away until the finalizer below destroys the GLXContext
(g_object_ref display)
(unless (and gtk3? (not widget)) (g_object_ref drawable))
(register-finalizer
ctxt
(λ (ctxt)
(define gl (send ctxt get-handle))
(define display (send ctxt get-gtk-display))
(define drawable (send ctxt get-gtk-drawable))
(define pixmap (send ctxt get-glx-pixmap))
(define xdisplay (gdk_x11_display_get_xdisplay display))
(when pixmap (glXDestroyGLXPixmap xdisplay pixmap))
(glXDestroyContext xdisplay gl)
(unless (and gtk3? (not widget)) (g_object_unref drawable))
(g_object_unref display)))
ctxt]
[else #f])]))
(define (make-gtk-widget-gl-context widget conf)
(atomically
(make-gtk-drawable-gl-context widget (widget-window widget) conf #t)))
(define (make-gtk-pixmap-gl-context pixmap conf)
(atomically
(make-gtk-drawable-gl-context #f pixmap conf #f)))
;; ===================================================================================================
(define widget-config-hash (make-weak-hasheq))
(define (prepare-widget-gl-context widget conf)
(hash-set! widget-config-hash widget (if conf conf (make-object gl-config%))))
(define (create-widget-gl-context widget)
(define conf (hash-ref widget-config-hash widget #f))
(and conf (make-gtk-widget-gl-context widget conf)))
(define-local-member-name
get-gdk-pixmap
install-gl-context)
(define (create-and-install-gl-context bm conf)
(define ctxt (make-gtk-pixmap-gl-context (send bm get-gdk-pixmap) conf))
(and ctxt (send bm install-gl-context ctxt)))