[Mesa-dev] [PATCH 18/20] glx: Enable GLX_EXT_create_context_es2_profile

[Ian Romanick]

From: Ian Romanick <ian.d.romanick at intel.com>

This extension is only enabled if the underlying driver advertises
support for OpenGL ES 2.0.  This happens either through the getAPIMask
function in version 2 of the DRI2 extension or implicity through
version 2 of the DRISW extension.

Since there is no OpenGL ES 2.0 protocol, this extension is marked as
only available with direct-rendering.

Signed-off-by: Ian Romanick <ian.d.romanick at intel.com>
---
 src/glx/dri2_glx.c      |    6 ++++++
 src/glx/dri_common.c    |   16 ++++++++++++++++
 src/glx/drisw_glx.c     |    5 +++++
 src/glx/glxextensions.c |   11 +++++++++++
 src/glx/glxextensions.h |    1 +
 5 files changed, 39 insertions(+), 0 deletions(-)

diff --git a/src/glx/dri2_glx.c b/src/glx/dri2_glx.c
index 54fea6f..51d45c9 100644
--- a/src/glx/dri2_glx.c
+++ b/src/glx/dri2_glx.c
@@ -923,8 +923,14 @@ dri2BindExtensions(struct dri2_screen *psc, const __DRIextension **extensions)
    __glXEnableDirectExtension(&psc->base, "INTEL_swap_event");
 
    if (psc->dri2->base.version >= 3) {
+      const unsigned mask = psc->dri2->getAPIMask(psc->driScreen);
+
       __glXEnableDirectExtension(&psc->base, "GLX_ARB_create_context");
       __glXEnableDirectExtension(&psc->base, "GLX_ARB_create_context_profile");
+
+      if ((mask & (1 << __DRI_API_GLES2)) != 0)
+	 __glXEnableDirectExtension(&psc->base,
+				    "GLX_EXT_create_context_es2_profile");
    }
 
    for (i = 0; extensions[i]; i++) {
diff --git a/src/glx/dri_common.c b/src/glx/dri_common.c
index 5d50aa9..8feb587 100644
--- a/src/glx/dri_common.c
+++ b/src/glx/dri_common.c
@@ -488,6 +488,9 @@ dri2_convert_glx_attribs(unsigned num_attribs, const uint32_t *attribs,
       case GLX_CONTEXT_COMPATIBILITY_PROFILE_BIT_ARB:
 	 *api = __DRI_API_OPENGL;
 	 break;
+      case GLX_CONTEXT_ES2_PROFILE_BIT_EXT:
+	 *api = __DRI_API_GLES2;
+	 break;
       default:
 	 *error = __DRI_CTX_ERROR_BAD_API;
 	 return false;
@@ -517,6 +520,19 @@ dri2_convert_glx_attribs(unsigned num_attribs, const uint32_t *attribs,
       return false;
    }
 
+   /* The GLX_EXT_create_context_es2_profile spec says:
+    *
+    *     "... If the version requested is 2.0, and the
+    *     GLX_CONTEXT_ES2_PROFILE_BIT_EXT bit is set in the
+    *     GLX_CONTEXT_PROFILE_MASK_ARB attribute (see below), then the context
+    *     returned will implement OpenGL ES 2.0. This is the only way in which
+    *     an implementation may request an OpenGL ES 2.0 context."
+    */
+   if (*api == __DRI_API_GLES2 && (*major_ver != 2 || *minor_ver != 0)) {
+      *error = __DRI_CTX_ERROR_BAD_API;
+      return false;
+   }
+
    *error = __DRI_CTX_ERROR_SUCCESS;
    return true;
 }
diff --git a/src/glx/drisw_glx.c b/src/glx/drisw_glx.c
index cb7f79c..2d83a50 100644
--- a/src/glx/drisw_glx.c
+++ b/src/glx/drisw_glx.c
@@ -598,6 +598,11 @@ driswBindExtensions(struct drisw_screen *psc, const __DRIextension **extensions)
    if (psc->swrast->base.version >= 3) {
       __glXEnableDirectExtension(&psc->base, "GLX_ARB_create_context");
       __glXEnableDirectExtension(&psc->base, "GLX_ARB_create_context_profile");
+
+      /* DRISW version >= 2 implies support for OpenGL ES 2.0.
+       */
+      __glXEnableDirectExtension(&psc->base,
+				 "GLX_EXT_create_context_es2_profile");
    }
 
    /* FIXME: Figure out what other extensions can be ported here from dri2. */
diff --git a/src/glx/glxextensions.c b/src/glx/glxextensions.c
index df5ef5c..73b84dc 100644
--- a/src/glx/glxextensions.c
+++ b/src/glx/glxextensions.c
@@ -80,6 +80,7 @@ static const struct extension_info known_glx_extensions[] = {
    { GLX(EXT_visual_info),             VER(0,0), Y, Y, N, N },
    { GLX(EXT_visual_rating),           VER(0,0), Y, Y, N, N },
    { GLX(EXT_framebuffer_sRGB),        VER(0,0), Y, Y, N, N },
+   { GLX(EXT_create_context_es2_profile), VER(0,0), Y, N, N, Y },
    { GLX(MESA_copy_sub_buffer),        VER(0,0), Y, N, N, N },
    { GLX(MESA_multithread_makecurrent),VER(0,0), Y, N, Y, N },
    { GLX(MESA_swap_control),           VER(0,0), Y, N, N, Y },
@@ -620,6 +621,16 @@ __glXCalculateUsableExtensions(struct glx_screen * psc,
       }
    }
 
+   /* This hack is necessary because GLX_ARB_create_context_profile depends on
+    * server support, but GLX_EXT_create_context_es2_profile is direct-only.
+    * Without this hack, it would be possible to advertise
+    * GLX_EXT_create_context_es2_profile without
+    * GLX_ARB_create_context_profile.  That would be a problem.
+    */
+   if (!IS_SET(server_support, ARB_create_context_profile_bit)) {
+      CLR_BIT(usable, EXT_create_context_es2_profile_bit);
+   }
+
    psc->effectiveGLXexts = __glXGetStringFromTable(known_glx_extensions,
                                                    usable);
 }
diff --git a/src/glx/glxextensions.h b/src/glx/glxextensions.h
index f432fdb..cad69a8 100644
--- a/src/glx/glxextensions.h
+++ b/src/glx/glxextensions.h
@@ -42,6 +42,7 @@ enum
    EXT_visual_rating_bit,
    EXT_import_context_bit,
    EXT_framebuffer_sRGB_bit,
+   EXT_create_context_es2_profile_bit,
    MESA_copy_sub_buffer_bit,
    MESA_depth_float_bit,
    MESA_multithread_makecurrent_bit,
-- 
1.7.6.4