Add an extension for requesting a NULL Display.

extensions/ANGLE_platform_angle_null.txt

+Name
+
+    ANGLE_platform_angle_null
+
+Name Strings
+
+    EGL_ANGLE_platform_angle_null
+
+Contributors
+
+    Geoff Lang, Google
+
+Contacts
+
+    Geoff Lang, Google (geofflang 'at' google 'dot' com)
+
+Status
+
+    Draft
+
+Version
+
+    Version 1, September 23, 2016
+
+Number
+
+    EGL Extension #??
+
+Extension Type
+
+    EGL client extension
+
+Dependencies
+
+    Requires ANGLE_platform_angle.
+
+Overview
+
+    This extension enables selection of null display types which perform state
+    tracking and validation but do not render any content.
+
+New Types
+
+    None
+
+New Procedures and Functions
+
+    None
+
+New Tokens
+
+    Accepted as values for the EGL_PLATFORM_ANGLE_TYPE_ANGLE attribute:
+
+        EGL_PLATFORM_ANGLE_TYPE_NULL_ANGLE               0x33AE
+
+Additions to the EGL Specification
+
+    None.
+
+New Behavior
+
+    To request a display that performs no rendering and has no platform
+    dependencies, the value of EGL_PLATFORM_ANGLE_TYPE_ANGLE should be
+    EGL_PLATFORM_ANGLE_TYPE_NULL_ANGLE.
+
+Issues
+
+    None
+
+Revision History
+
+    Version 1, 2016-09-23 (Geoff Lang)
+      - Initial draft

include/EGL/eglext.h

@@ -526,6 +526,11 @@ EGLAPI EGLBoolean EGLAPIENTRY eglQuerySurfacePointerANGLE (EGLDisplay dpy, EGLSu
 #define EGL_PLATFORM_ANGLE_TYPE_OPENGLES_ANGLE 0x320E
 #endif /* EGL_ANGLE_platform_angle_opengl */
 
+#ifndef EGL_ANGLE_platform_angle_null
+#define EGL_ANGLE_platform_angle_null 1
+#define EGL_PLATFORM_ANGLE_TYPE_NULL_ANGLE 0x33AE
+#endif /* EGL_ANGLE_platform_angle_null */
+
 #ifndef EGL_ANGLE_window_fixed_size
 #define EGL_ANGLE_window_fixed_size 1
 #define EGL_FIXED_SIZE_ANGLE              0x3201

src/libANGLE/Caps.cpp

@@ -867,6 +867,7 @@ std::vector<std::string> ClientExtensions::getStrings() const
     InsertExtensionString("EGL_ANGLE_platform_angle",              platformANGLE,             &extensionStrings);
     InsertExtensionString("EGL_ANGLE_platform_angle_d3d",          platformANGLED3D,          &extensionStrings);
     InsertExtensionString("EGL_ANGLE_platform_angle_opengl",       platformANGLEOpenGL,       &extensionStrings);
+    InsertExtensionString("EGL_ANGLE_platform_angle_null",         platformANGLENULL,         &extensionStrings);
     InsertExtensionString("EGL_ANGLE_device_creation",             deviceCreation,            &extensionStrings);
     InsertExtensionString("EGL_ANGLE_device_creation_d3d11",       deviceCreationD3D11,       &extensionStrings);
     InsertExtensionString("EGL_ANGLE_x11_visual",                  x11Visual,                 &extensionStrings);

src/libANGLE/Caps.h

@@ -639,6 +639,9 @@ struct ClientExtensions
     // EGL_ANGLE_platform_angle_opengl
     bool platformANGLEOpenGL;
 
+    // EGL_ANGLE_platform_angle_null
+    bool platformANGLENULL;
+
     // EGL_ANGLE_device_creation
     bool deviceCreation;
 

src/libANGLE/Display.cpp

@@ -53,6 +53,10 @@
 #   endif
 #endif
 
+#if defined(ANGLE_ENABLE_NULL)
+#include "libANGLE/renderer/null/DisplayNULL.h"
+#endif
+
 namespace egl
 {
 
@@ -209,6 +213,12 @@ rx::DisplayImpl *CreateDisplayFromAttribs(const AttributeMap &attribMap)
         break;
 #endif
 
+#if defined(ANGLE_ENABLE_NULL)
+      case EGL_PLATFORM_ANGLE_TYPE_NULL_ANGLE:
+          impl = new rx::DisplayNULL();
+          break;
+#endif
+
       default:
         UNREACHABLE();
         break;
@@ -874,6 +884,10 @@ static ClientExtensions GenerateClientExtensions()
     extensions.platformANGLEOpenGL = true;
 #endif
 
+#if defined(ANGLE_ENABLE_NULL)
+    extensions.platformANGLENULL = true;
+#endif
+
 #if defined(ANGLE_ENABLE_D3D11)
     extensions.deviceCreation      = true;
     extensions.deviceCreationD3D11 = true;

src/libGLESv2/entry_points_egl_ext.cpp

@@ -197,6 +197,17 @@ EGLDisplay EGLAPIENTRY GetPlatformDisplayEXT(EGLenum platform, void *native_disp
                             }
                             break;
 
+                        case EGL_PLATFORM_ANGLE_DEVICE_TYPE_NULL_ANGLE:
+                            if (!clientExtensions.platformANGLENULL)
+                            {
+                                SetGlobalError(Error(EGL_BAD_ATTRIBUTE,
+                                                     "Display type "
+                                                     "EGL_PLATFORM_ANGLE_DEVICE_TYPE_NULL_ANGLE "
+                                                     "requires EGL_ANGLE_platform_angle_null."));
+                                return EGL_NO_DISPLAY;
+                            }
+                            break;
+
                         default:
                         SetGlobalError(Error(EGL_BAD_ATTRIBUTE));
                         return EGL_NO_DISPLAY;