[cogl/cogl-1.16] Adds "webgl" driver

[Robert Bragg <rbragg src gnome org>]

commit 3fc1a39db886fe1e42362856c7708c70d74f787b
Author: Robert Bragg <robert linux intel com>
Date:   Sat May 11 20:02:43 2013 +0100

    Adds "webgl" driver
    
    This adds a COGL_DRIVER_WEBGL enum and a new driver description for
    webgl in cogl-renderer.c. This also adds a COGL_DRIVER_FLAG_OPENGL_WEB
    driver flag and a HAVE_COGL_WEBGL define which we can start to use to
    handle special cases where webgl differs from gles2.
    
    Reviewed-by: Neil Roberts <neil linux intel com>
    
    (cherry picked from commit 2c167b7a4ee56241827322bbe7cb287b0628437c)

 cogl/cogl-private.h  |    3 ++-
 cogl/cogl-renderer.c |   16 ++++++++++++++++
 cogl/cogl-renderer.h |    4 +++-
 configure.ac         |    1 +
 4 files changed, 22 insertions(+), 2 deletions(-)
---
diff --git a/cogl/cogl-private.h b/cogl/cogl-private.h
index 6bc51ea..5dee8e3 100644
--- a/cogl/cogl-private.h
+++ b/cogl/cogl-private.h
@@ -68,7 +68,8 @@ typedef enum
   COGL_PRIVATE_FEATURE_ANY_GL = 1L<<26,
   COGL_PRIVATE_FEATURE_GL_FIXED = 1L<<27,
   COGL_PRIVATE_FEATURE_GL_PROGRAMMABLE = 1L<<28,
-  COGL_PRIVATE_FEATURE_GL_EMBEDDED = 1L<<29
+  COGL_PRIVATE_FEATURE_GL_EMBEDDED = 1L<<29,
+  COGL_PRIVATE_FEATURE_GL_WEB = 1L<<30
 } CoglPrivateFeatureFlags;
 
 /* Sometimes when evaluating pipelines, either during comparisons or
diff --git a/cogl/cogl-renderer.c b/cogl/cogl-renderer.c
index 6360daf..fc207a8 100644
--- a/cogl/cogl-renderer.c
+++ b/cogl/cogl-renderer.c
@@ -156,6 +156,20 @@ static CoglDriverDescription _cogl_drivers[] =
     COGL_GLES1_LIBNAME,
   },
 #endif
+#ifdef USING_EMSCRIPTEN
+  {
+    COGL_DRIVER_WEBGL,
+    "webgl",
+    0,
+    COGL_PRIVATE_FEATURE_ANY_GL |
+      COGL_PRIVATE_FEATURE_GL_EMBEDDED |
+      COGL_PRIVATE_FEATURE_GL_PROGRAMMABLE |
+      COGL_PRIVATE_FEATURE_GL_WEB,
+    &_cogl_driver_gles,
+    &_cogl_texture_driver_gles,
+    NULL,
+  },
+#endif
   {
     COGL_DRIVER_NOP,
     "nop",
@@ -425,6 +439,8 @@ driver_id_to_name (CoglDriver id)
         return "gles1";
       case COGL_DRIVER_GLES2:
         return "gles2";
+      case COGL_DRIVER_WEBGL:
+        return "webgl";
       case COGL_DRIVER_NOP:
         return "nop";
       case COGL_DRIVER_ANY:
diff --git a/cogl/cogl-renderer.h b/cogl/cogl-renderer.h
index 45a8d74..d913cb2 100644
--- a/cogl/cogl-renderer.h
+++ b/cogl/cogl-renderer.h
@@ -332,6 +332,7 @@ cogl_renderer_remove_constraint (CoglRenderer *renderer,
  * @COGL_DRIVER_GL3: An OpenGL driver using the core GL 3.1 profile
  * @COGL_DRIVER_GLES1: An OpenGL ES 1.1 driver.
  * @COGL_DRIVER_GLES2: An OpenGL ES 2.0 driver.
+ * @COGL_DRIVER_WEBGL: A WebGL driver.
  *
  * Identifiers for underlying hardware drivers that may be used by
  * Cogl for rendering.
@@ -346,7 +347,8 @@ typedef enum
   COGL_DRIVER_GL,
   COGL_DRIVER_GL3,
   COGL_DRIVER_GLES1,
-  COGL_DRIVER_GLES2
+  COGL_DRIVER_GLES2,
+  COGL_DRIVER_WEBGL
 } CoglDriver;
 
 /**
diff --git a/configure.ac b/configure.ac
index 5cf0cf4..91d3b2f 100644
--- a/configure.ac
+++ b/configure.ac
@@ -731,6 +731,7 @@ AS_IF([test "x$enable_gles2" = "xyes"],
               [
                 GL_LIBRARY_DIRECTLY_LINKED=yes
                 COGL_GLES2_LIBNAME=""
+                AC_DEFINE([HAVE_COGL_WEBGL], 1, [Have WebGL for rendering])
               ],
 
               [