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/* cairo - a vector graphics library with display and print output
*
* Copyright © 2009 Eric Anholt
* Copyright © 2009 Chris Wilson
* Copyright © 2005 Red Hat, Inc
*
* This library is free software; you can redistribute it and/or
* modify it either under the terms of the GNU Lesser General Public
* License version 2.1 as published by the Free Software Foundation
* (the "LGPL") or, at your option, under the terms of the Mozilla
* Public License Version 1.1 (the "MPL"). If you do not alter this
* notice, a recipient may use your version of this file under either
* the MPL or the LGPL.
*
* You should have received a copy of the LGPL along with this library
* in the file COPYING-LGPL-2.1; if not, write to the Free Software
* Foundation, Inc., 51 Franklin Street, Suite 500, Boston, MA 02110-1335, USA
* You should have received a copy of the MPL along with this library
* in the file COPYING-MPL-1.1
*
* The contents of this file are subject to the Mozilla Public License
* Version 1.1 (the "License"); you may not use this file except in
* compliance with the License. You may obtain a copy of the License at
*
* This software is distributed on an "AS IS" basis, WITHOUT WARRANTY
* OF ANY KIND, either express or implied. See the LGPL or the MPL for
* the specific language governing rights and limitations.
*
* The Original Code is the cairo graphics library.
*
* The Initial Developer of the Original Code is Red Hat, Inc.
*
* Contributor(s):
* Carl Worth <cworth@cworth.org>
* Chris Wilson <chris@chris-wilson.co.uk>
*/
#include "cairoint.h"
#include "cairo-gl-private.h"
#include "cairo-error-private.h"
#include <X11/Xutil.h>
/* XXX needs hooking into XCloseDisplay() */
typedef struct _cairo_glx_context {
cairo_gl_context_t base;
Display *display;
Window dummy_window;
GLXContext context;
GLXDrawable previous_drawable;
GLXContext previous_context;
cairo_bool_t has_multithread_makecurrent;
} cairo_glx_context_t;
typedef struct _cairo_glx_surface {
cairo_gl_surface_t base;
Window win;
} cairo_glx_surface_t;
static cairo_bool_t
_context_acquisition_changed_glx_state (cairo_glx_context_t *ctx,
GLXDrawable current_drawable)
{
return ctx->previous_drawable != current_drawable ||
ctx->previous_context != ctx->context;
}
static GLXDrawable
_glx_get_current_drawable (cairo_glx_context_t *ctx)
{
if (ctx->base.current_target == NULL ||
_cairo_gl_surface_is_texture (ctx->base.current_target)) {
return ctx->dummy_window;
}
return ((cairo_glx_surface_t *) ctx->base.current_target)->win;
}
static void
_glx_query_current_state (cairo_glx_context_t * ctx)
{
ctx->previous_drawable = glXGetCurrentDrawable ();
ctx->previous_context = glXGetCurrentContext ();
/* If any of the values were none, assume they are all none. Not all
drivers seem well behaved when it comes to using these values across
multiple threads. */
if (ctx->previous_drawable == None ||
ctx->previous_context == None) {
ctx->previous_drawable = None;
ctx->previous_context = None;
}
}
static void
_glx_acquire (void *abstract_ctx)
{
cairo_glx_context_t *ctx = abstract_ctx;
GLXDrawable current_drawable = _glx_get_current_drawable (ctx);
_glx_query_current_state (ctx);
if (!_context_acquisition_changed_glx_state (ctx, current_drawable))
return;
glXMakeCurrent (ctx->display, current_drawable, ctx->context);
}
static void
_glx_make_current (void *abstract_ctx, cairo_gl_surface_t *abstract_surface)
{
cairo_glx_context_t *ctx = abstract_ctx;
cairo_glx_surface_t *surface = (cairo_glx_surface_t *) abstract_surface;
/* Set the window as the target of our context. */
glXMakeCurrent (ctx->display, surface->win, ctx->context);
}
static void
_glx_release (void *abstract_ctx)
{
cairo_glx_context_t *ctx = abstract_ctx;
if (ctx->has_multithread_makecurrent || !ctx->base.thread_aware ||
!_context_acquisition_changed_glx_state (ctx,
_glx_get_current_drawable (ctx))) {
return;
}
glXMakeCurrent (ctx->display, None, None);
}
static void
_glx_swap_buffers (void *abstract_ctx,
cairo_gl_surface_t *abstract_surface)
{
cairo_glx_context_t *ctx = abstract_ctx;
cairo_glx_surface_t *surface = (cairo_glx_surface_t *) abstract_surface;
glXSwapBuffers (ctx->display, surface->win);
}
static void
_glx_destroy (void *abstract_ctx)
{
cairo_glx_context_t *ctx = abstract_ctx;
if (ctx->dummy_window != None)
XDestroyWindow (ctx->display, ctx->dummy_window);
glXMakeCurrent (ctx->display, None, None);
}
static cairo_status_t
_glx_dummy_window (Display *dpy, GLXContext gl_ctx, Window *dummy)
{
int attr[3] = { GLX_FBCONFIG_ID, 0, None };
GLXFBConfig *config;
XVisualInfo *vi;
Colormap cmap;
XSetWindowAttributes swa;
Window win = None;
int cnt;
/* Create a dummy window created for the target GLX context that we can
* use to query the available GL/GLX extensions.
*/
glXQueryContext (dpy, gl_ctx, GLX_FBCONFIG_ID, &attr[1]);
cnt = 0;
config = glXChooseFBConfig (dpy, DefaultScreen (dpy), attr, &cnt);
if (unlikely (cnt == 0))
return _cairo_error (CAIRO_STATUS_INVALID_FORMAT);
vi = glXGetVisualFromFBConfig (dpy, config[0]);
XFree (config);
if (unlikely (vi == NULL))
return _cairo_error (CAIRO_STATUS_INVALID_FORMAT);
cmap = XCreateColormap (dpy,
RootWindow (dpy, vi->screen),
vi->visual,
AllocNone);
swa.colormap = cmap;
swa.border_pixel = 0;
win = XCreateWindow (dpy, RootWindow (dpy, vi->screen),
-1, -1, 1, 1, 0,
vi->depth,
InputOutput,
vi->visual,
CWBorderPixel | CWColormap, &swa);
XFreeColormap (dpy, cmap);
XFree (vi);
XFlush (dpy);
if (unlikely (! glXMakeCurrent (dpy, win, gl_ctx))) {
XDestroyWindow (dpy, win);
return _cairo_error (CAIRO_STATUS_NO_MEMORY);
}
*dummy = win;
return CAIRO_STATUS_SUCCESS;
}
cairo_device_t *
cairo_glx_device_create (Display *dpy, GLXContext gl_ctx)
{
cairo_glx_context_t *ctx;
cairo_status_t status;
Window dummy = None;
const char *glx_extensions;
ctx = calloc (1, sizeof (cairo_glx_context_t));
if (unlikely (ctx == NULL))
return _cairo_gl_context_create_in_error (CAIRO_STATUS_NO_MEMORY);
/* glx_dummy_window will call glXMakeCurrent, so we need to
* query the current state of the context now. */
_glx_query_current_state (ctx);
status = _glx_dummy_window (dpy, gl_ctx, &dummy);
if (unlikely (status)) {
free (ctx);
return _cairo_gl_context_create_in_error (status);
}
ctx->display = dpy;
ctx->dummy_window = dummy;
ctx->context = gl_ctx;
ctx->base.acquire = _glx_acquire;
ctx->base.release = _glx_release;
ctx->base.make_current = _glx_make_current;
ctx->base.swap_buffers = _glx_swap_buffers;
ctx->base.destroy = _glx_destroy;
status = _cairo_gl_dispatch_init (&ctx->base.dispatch,
(cairo_gl_get_proc_addr_func_t) glXGetProcAddress);
if (unlikely (status)) {
free (ctx);
return _cairo_gl_context_create_in_error (status);
}
status = _cairo_gl_context_init (&ctx->base);
if (unlikely (status)) {
free (ctx);
return _cairo_gl_context_create_in_error (status);
}
glx_extensions = glXQueryExtensionsString (dpy, DefaultScreen (dpy));
if (strstr(glx_extensions, "GLX_MESA_multithread_makecurrent")) {
ctx->has_multithread_makecurrent = TRUE;
}
ctx->base.release (ctx);
return &ctx->base.base;
}
Display *
cairo_glx_device_get_display (cairo_device_t *device)
{
cairo_glx_context_t *ctx;
if (device->backend->type != CAIRO_DEVICE_TYPE_GL) {
_cairo_error_throw (CAIRO_STATUS_DEVICE_TYPE_MISMATCH);
return NULL;
}
ctx = (cairo_glx_context_t *) device;
return ctx->display;
}
GLXContext
cairo_glx_device_get_context (cairo_device_t *device)
{
cairo_glx_context_t *ctx;
if (device->backend->type != CAIRO_DEVICE_TYPE_GL) {
_cairo_error_throw (CAIRO_STATUS_DEVICE_TYPE_MISMATCH);
return NULL;
}
ctx = (cairo_glx_context_t *) device;
return ctx->context;
}
cairo_surface_t *
cairo_gl_surface_create_for_window (cairo_device_t *device,
Window win,
int width,
int height)
{
cairo_glx_surface_t *surface;
if (unlikely (device->status))
return _cairo_surface_create_in_error (device->status);
if (device->backend->type != CAIRO_DEVICE_TYPE_GL)
return _cairo_surface_create_in_error (_cairo_error (CAIRO_STATUS_SURFACE_TYPE_MISMATCH));
if (width <= 0 || height <= 0)
return _cairo_surface_create_in_error (_cairo_error (CAIRO_STATUS_INVALID_SIZE));
surface = calloc (1, sizeof (cairo_glx_surface_t));
if (unlikely (surface == NULL))
return _cairo_surface_create_in_error (_cairo_error (CAIRO_STATUS_NO_MEMORY));
_cairo_gl_surface_init (device, &surface->base,
CAIRO_CONTENT_COLOR_ALPHA, width, height);
surface->win = win;
return &surface->base.base;
}