gl-renderer: use eglGetPlatformDisplayEXT to get an EGLDisplay

Reviewed-by: Derek Foreman <derekf@osg.samsung.com>
Reviewed-by: Bryce Harrington <bryce@osg.samsung.com>

src/compositor-drm.c

@@ -52,6 +52,8 @@
 #include "vaapi-recorder.h"
 #include "presentation_timing-server-protocol.h"
 
+#include <EGL/eglext.h>
+
 #ifndef DRM_CAP_TIMESTAMP_MONOTONIC
 #define DRM_CAP_TIMESTAMP_MONOTONIC 0x6
 #endif
@@ -68,6 +70,10 @@
 #define GBM_BO_USE_CURSOR GBM_BO_USE_CURSOR_64X64
 #endif
 
+#ifndef EGL_PLATFORM_GBM_KHR
+#define EGL_PLATFORM_GBM_KHR 0x31D7
+#endif
+
 static int option_current_mode = 0;
 
 enum output_config {
@@ -1396,8 +1402,13 @@ drm_compositor_create_gl_renderer(struct drm_compositor *ec)
 {
 	EGLint format;
 
+	if (!gl_renderer->supports ||
+	    gl_renderer->supports(&ec->base, "gbm") < 0) {
+		return -1;
+	}
+
 	format = ec->format;
-	if (gl_renderer->create(&ec->base, ec->gbm,
+	if (gl_renderer->create(&ec->base, EGL_PLATFORM_GBM_KHR, (void *) ec->gbm,
 			       gl_renderer->opaque_attribs, &format) < 0) {
 		return -1;
 	}

src/compositor-fbdev.c

@@ -868,7 +868,7 @@ fbdev_compositor_create(struct wl_display *display, int *argc, char *argv[],
 			goto out_launcher;
 		}
 
-		if (gl_renderer->create(&compositor->base, EGL_DEFAULT_DISPLAY,
+		if (gl_renderer->create(&compositor->base, 0, EGL_DEFAULT_DISPLAY,
 					gl_renderer->opaque_attribs,
 					NULL) < 0) {
 			weston_log("gl_renderer_create failed.\n");

src/compositor-wayland.c

@@ -45,8 +45,14 @@
 #include "fullscreen-shell-client-protocol.h"
 #include "presentation_timing-server-protocol.h"
 
+#include <EGL/eglext.h>
+
 #define WINDOW_TITLE "Weston Compositor"
 
+#ifndef EGL_PLATFORM_WAYLAND_KHR
+#define EGL_PLATFORM_WAYLAND_KHR 0x31D8
+#endif
+
 struct wayland_compositor {
 	struct weston_compositor base;
 
@@ -1961,9 +1967,17 @@ wayland_compositor_create(struct wl_display *display, int use_pixman,
 	}
 
 	if (!c->use_pixman) {
-		if (gl_renderer->create(&c->base, c->parent.wl_display,
+		if (!gl_renderer->supports ||
-				gl_renderer->alpha_attribs,
+		    gl_renderer->supports(&c->base, "wayland") < 0) {
-				NULL) < 0) {
+			weston_log("No support for "
+			           "EGL_{KHR,EXT,MESA}_platform_wayland; "
+			           "falling back to pixman.\n");
+			c->use_pixman = 1;
+		} else if (gl_renderer->create(&c->base,
+					       EGL_PLATFORM_WAYLAND_KHR,
+					       c->parent.wl_display,
+					       gl_renderer->alpha_attribs,
+					       NULL) < 0) {
 			weston_log("Failed to initialize the GL renderer; "
 				   "falling back to pixman.\n");
 			c->use_pixman = 1;

src/compositor-x11.c

@@ -53,8 +53,14 @@
 #include "../shared/image-loader.h"
 #include "presentation_timing-server-protocol.h"
 
+#include <EGL/eglext.h>
+
 #define DEFAULT_AXIS_STEP_DISTANCE wl_fixed_from_int(10)
 
+#ifndef EGL_PLATFORM_X11_KHR
+#define EGL_PLATFORM_X11_KHR 0x31D5
+#endif
+
 static int option_width;
 static int option_height;
 static int option_scale;
@@ -1487,7 +1493,10 @@ init_gl_renderer(struct x11_compositor *c)
 	if (!gl_renderer)
 		return -1;
 
-	ret = gl_renderer->create(&c->base, (EGLNativeDisplayType) c->dpy,
+	if (!gl_renderer->supports || gl_renderer->supports(&c->base, "x11") < 0)
+		return -1;
+
+	ret = gl_renderer->create(&c->base, EGL_PLATFORM_X11_KHR, (void *) c->dpy,
 				  gl_renderer->opaque_attribs, NULL);
 
 	return ret;

src/gl-renderer.c

@@ -166,6 +166,10 @@ struct gl_renderer {
 	struct wl_signal destroy_signal;
 };
 
+#ifdef EGL_EXT_platform_base
+static PFNEGLGETPLATFORMDISPLAYEXTPROC get_platform_display = NULL;
+#endif
+
 static inline struct gl_output_state *
 get_output_state(struct weston_output *output)
 {
@@ -2148,9 +2152,69 @@ static const EGLint gl_renderer_alpha_attribs[] = {
 	EGL_NONE
 };
 
+/** Checks whether a platform EGL client extension is supported
+ *
+ * \param ec The weston compositor
+ * \param extension_suffix The EGL client extension suffix
+ * \return 1 if supported, 0 if using fallbacks, -1 unsupported
+ *
+ * This function checks whether a specific platform_* extension is supported
+ * by EGL.
+ *
+ * The extension suffix should be the suffix of the platform extension (that
+ * specifies a <platform> argument as defined in EGL_EXT_platform_base). For
+ * example, passing "foo" will check whether either "EGL_KHR_platform_foo",
+ * "EGL_EXT_platform_foo", or "EGL_MESA_platform_foo" is supported.
+ *
+ * The return value is 1:
+ *   - if the supplied EGL client extension is supported.
+ * The return value is 0:
+ *   - if the platform_base client extension isn't supported so will
+ *     fallback to eglGetDisplay and friends.
+ * The return value is -1:
+ *   - if the supplied EGL client extension is not supported.
+ */
 static int
-gl_renderer_create(struct weston_compositor *ec, EGLNativeDisplayType display,
+gl_renderer_supports(struct weston_compositor *ec,
-	const EGLint *attribs, const EGLint *visual_id)
+		     const char *extension_suffix)
+{
+	static const char *extensions = NULL;
+	char s[64];
+
+	if (!extensions) {
+		extensions = (const char *) eglQueryString(
+			EGL_NO_DISPLAY, EGL_EXTENSIONS);
+
+		if (!extensions)
+			return 0;
+
+		log_extensions("EGL client extensions",
+			       extensions);
+	}
+
+	snprintf(s, sizeof s, "EGL_KHR_platform_%s", extension_suffix);
+	if (strstr(extensions, s))
+		return 1;
+
+	snprintf(s, sizeof s, "EGL_EXT_platform_%s", extension_suffix);
+	if (strstr(extensions, s))
+		return 1;
+
+	snprintf(s, sizeof s, "EGL_MESA_platform_%s", extension_suffix);
+	if (strstr(extensions, s))
+		return 1;
+
+	/* at this point we definitely have some client extensions but
+	 * haven't found the supplied client extension, so chances are it's
+	 * not supported. */
+
+	return -1;
+}
+
+static int
+gl_renderer_create(struct weston_compositor *ec, EGLenum platform,
+	void *native_window, const EGLint *attribs,
+	const EGLint *visual_id)
 {
 	struct gl_renderer *gr;
 	EGLint major, minor;
@@ -2169,7 +2233,26 @@ gl_renderer_create(struct weston_compositor *ec, EGLNativeDisplayType display,
 		gl_renderer_surface_get_content_size;
 	gr->base.surface_copy_content = gl_renderer_surface_copy_content;
 
-	gr->egl_display = eglGetDisplay(display);
+#ifdef EGL_EXT_platform_base
+	if (!get_platform_display) {
+		get_platform_display =
+			(void *) eglGetProcAddress("eglGetPlatformDisplayEXT");
+	}
+
+	if (get_platform_display && platform) {
+		gr->egl_display =
+			get_platform_display(platform, native_window,
+					     NULL);
+	} else {
+#endif
+		weston_log("warning: either no EGL_EXT_platform_base "
+			   "support or specific platform support; "
+			   "falling back to eglGetDisplay.\n");
+		gr->egl_display = eglGetDisplay(native_window);
+#ifdef EGL_EXT_platform_base
+	}
+#endif
+
 	if (gr->egl_display == EGL_NO_DISPLAY) {
 		weston_log("failed to create display\n");
 		goto err_egl;
@@ -2381,6 +2464,7 @@ WL_EXPORT struct gl_renderer_interface gl_renderer_interface = {
 	.opaque_attribs = gl_renderer_opaque_attribs,
 	.alpha_attribs = gl_renderer_alpha_attribs,
 
+	.supports = gl_renderer_supports,
 	.create = gl_renderer_create,
 	.display = gl_renderer_display,
 	.output_create = gl_renderer_output_create,

src/gl-renderer.h

@@ -50,8 +50,12 @@ struct gl_renderer_interface {
 	const EGLint *opaque_attribs;
 	const EGLint *alpha_attribs;
 
+	int (*supports)(struct weston_compositor *ec,
+			const char *extension_suffix);
+
 	int (*create)(struct weston_compositor *ec,
-		      EGLNativeDisplayType display,
+		      EGLenum platform,
+		      void *native_window,
 		      const EGLint *attribs,
 		      const EGLint *visual_id);