GL: implemente ANGLE_provoking_vertex and ANGLE_polygon_mode on ES.

No WebGL support yet as Emscripten doesn't have the required
entrypoints.

doc/opengl-support.dox

@@ -452,8 +452,8 @@ Extension                                   | Status
 @gl_extension2{ANGLE,texture_compression_dxt5,ANGLE_texture_compression_dxt} | done
 @m_class{m-doc-external} [ANGLE_multi_draw](https://chromium.googlesource.com/angle/angle/+/master/extensions/ANGLE_multi_draw.txt) (unlisted) | done
 @m_class{m-doc-external} [ANGLE_base_vertex_base_instance](https://chromium.googlesource.com/angle/angle/+/master/extensions/ANGLE_base_vertex_base_instance.txt) (unlisted) | done
-@m_class{m-doc-external} [ANGLE_provoking_vertex](https://chromium.googlesource.com/angle/angle/+/main/extensions/ANGLE_provoking_vertex.txt) (unlisted) | |
+@m_class{m-doc-external} [ANGLE_provoking_vertex](https://chromium.googlesource.com/angle/angle/+/main/extensions/ANGLE_provoking_vertex.txt) (unlisted) | done
-@m_class{m-doc-external} [ANGLE_polygon_mode](https://chromium.googlesource.com/angle/angle/+/HEAD/extensions/ANGLE_polygon_mode.txt) (unlisted) | |
+@m_class{m-doc-external} [ANGLE_polygon_mode](https://chromium.googlesource.com/angle/angle/+/HEAD/extensions/ANGLE_polygon_mode.txt) (unlisted) | done
 @m_class{m-doc-external} [ANGLE_stencil_texturing](https://chromium.googlesource.com/angle/angle/+/HEAD/extensions/ANGLE_stencil_texturing.txt) (unlisted) | |
 @gl_extension{APPLE,texture_format_BGRA8888} | done
 @gl_extension{APPLE,clip_distance}          | done

src/Magnum/GL/Implementation/RendererState.cpp

@@ -206,6 +206,20 @@ RendererState::RendererState(Context& context, ContextState& contextState, Conta
     #endif
     #endif
 
+    #if defined(MAGNUM_TARGET_GLES) && !defined(MAGNUM_TARGET_WEBGL)
+    if(context.isExtensionSupported<Extensions::NV::polygon_mode>()) {
+        extensions[Extensions::NV::polygon_mode::Index] =
+                   Extensions::NV::polygon_mode::string();
+        polygonModeImplementation = glPolygonModeNV;
+    } else if(context.isExtensionSupported<Extensions::ANGLE::polygon_mode>()) {
+        extensions[Extensions::ANGLE::polygon_mode::Index] =
+                   Extensions::ANGLE::polygon_mode::string();
+        polygonModeImplementation = glPolygonModeANGLE;
+    } else {
+        polygonModeImplementation = nullptr;
+    }
+    #endif
+
     #ifndef MAGNUM_TARGET_GLES
     /* On compatibility profile we need to explicitly enable GL_POINT_SPRITE
        in order to have gl_PointCoord working (on NVidia at least, Mesa behaves

src/Magnum/GL/Implementation/RendererState.h

@@ -59,6 +59,9 @@ struct RendererState {
     void(APIENTRY *blendFuncSeparateiImplementation)(GLuint, GLenum, GLenum, GLenum, GLenum);
     void(APIENTRY *colorMaskiImplementation)(GLuint, GLboolean, GLboolean, GLboolean, GLboolean);
     #endif
+    #if defined(MAGNUM_TARGET_GLES) && !defined(MAGNUM_TARGET_WEBGL)
+    void(APIENTRY *polygonModeImplementation)(GLenum, GLenum);
+    #endif
     #ifndef MAGNUM_TARGET_WEBGL
     GLenum(APIENTRY *graphicsResetStatusImplementation)();
 

src/Magnum/GL/Renderer.cpp

@@ -126,9 +126,14 @@ void Renderer::setFaceCullingMode(const PolygonFacing mode) {
     glCullFace(GLenum(mode));
 }
 
-#ifndef MAGNUM_TARGET_GLES
+#if !defined(MAGNUM_TARGET_GLES2) && !defined(MAGNUM_TARGET_WEBGL)
 void Renderer::setProvokingVertex(const ProvokingVertex mode) {
-    glProvokingVertex(GLenum(mode));
+    #ifndef MAGNUM_TARGET_GLES
+    glProvokingVertex
+    #else
+    glProvokingVertexANGLE
+    #endif
+        (GLenum(mode));
 }
 #endif
 
@@ -137,7 +142,7 @@ void Renderer::setPolygonMode(const PolygonMode mode) {
     #ifndef MAGNUM_TARGET_GLES
     glPolygonMode
     #else
-    glPolygonModeNV
+    Context::current().state().renderer.polygonModeImplementation
     #endif
         (GL_FRONT_AND_BACK, GLenum(mode));
 }

src/Magnum/GL/Renderer.h

@@ -411,6 +411,7 @@ class MAGNUM_GL_EXPORT Renderer {
              * @see @ref Feature::PolygonOffsetFill, @ref Feature::PolygonOffsetPoint,
              *      @ref setPolygonOffset()
              * @requires_es_extension Extension @gl_extension{NV,polygon_offset}
+             *      or @m_class{m-doc-external} [ANGLE_polygon_mode](https://chromium.googlesource.com/angle/angle/+/HEAD/extensions/ANGLE_polygon_mode.txt)
              * @requires_gles Only @ref Feature::PolygonOffsetFill is available
              *      in WebGL.
              */
@@ -796,7 +797,7 @@ class MAGNUM_GL_EXPORT Renderer {
          */
         static void setFaceCullingMode(PolygonFacing mode);
 
-        #ifndef MAGNUM_TARGET_GLES
+        #if !defined(MAGNUM_TARGET_GLES2) && !defined(MAGNUM_TARGET_WEBGL)
         /**
          * @brief Provoking vertex
          *
@@ -804,15 +805,27 @@ class MAGNUM_GL_EXPORT Renderer {
          * @m_enum_values_as_keywords
          * @requires_gl32 Extension @gl_extension{ARB,provoking_vertex}. Older
          *      versions behave always like @ref ProvokingVertex::LastVertexConvention.
-         * @requires_gl OpenGL ES and WebGL behave always like
+         * @requires_es_extension OpenGL ES 3.0 and extension
+         *      @m_class{m-doc-external} [ANGLE_provoking_vertex](https://chromium.googlesource.com/angle/angle/+/main/extensions/ANGLE_provoking_vertex.txt).
+         *      Without the extension behaves always like
+         *      @ref ProvokingVertex::LastVertexConvention.
+         * @requires_gles WebGL behaves always like
          *      @ref ProvokingVertex::LastVertexConvention.
          */
         enum class ProvokingVertex: GLenum {
             /** Use first vertex of each polygon. */
+            #ifndef MAGNUM_TARGET_GLES
             FirstVertexConvention = GL_FIRST_VERTEX_CONVENTION,
+            #else
+            FirstVertexConvention = GL_FIRST_VERTEX_CONVENTION_ANGLE,
+            #endif
 
             /** Use last vertex of each polygon (default). */
+            #ifndef MAGNUM_TARGET_GLES
             LastVertexConvention = GL_LAST_VERTEX_CONVENTION
+            #else
+            LastVertexConvention = GL_LAST_VERTEX_CONVENTION_ANGLE
+            #endif
         };
 
         /**
@@ -822,7 +835,9 @@ class MAGNUM_GL_EXPORT Renderer {
          * @see @fn_gl_keyword{ProvokingVertex}
          * @requires_gl32 Extension @gl_extension{ARB,provoking_vertex}. Older
          *      versions behave always like the default.
-         * @requires_gl OpenGL ES and WebGL behave always like the default.
+         * @requires_es_extension OpenGL ES 3.0 and extension
+         *      @m_class{m-doc-external} [ANGLE_provoking_vertex](https://chromium.googlesource.com/angle/angle/+/main/extensions/ANGLE_provoking_vertex.txt)
+         * @requires_gles WebGL behaves always like the default.
          */
         static void setProvokingVertex(ProvokingVertex mode);
         #endif
@@ -833,11 +848,12 @@ class MAGNUM_GL_EXPORT Renderer {
          *
          * @see @ref setPolygonMode()
          * @m_enum_values_as_keywords
-         * @requires_es_extension Extension @gl_extension{NV,polygon_mode}.
+         * @requires_es_extension Extension @gl_extension{NV,polygon_mode} or
+         *      @m_class{m-doc-external} [ANGLE_polygon_mode](https://chromium.googlesource.com/angle/angle/+/HEAD/extensions/ANGLE_polygon_mode.txt).
          *      Otherwise behaves always like @ref PolygonMode::Fill. See
-         *      @ref Mesh::setPrimitive() for possible workaround.
+         *      @ref Mesh::setPrimitive() for a possible workaround.
          * @requires_gles WebGL behaves always like @ref PolygonMode::Fill. See
-         *      @ref Mesh::setPrimitive() for possible workaround.
+         *      @ref Mesh::setPrimitive() for a possible workaround.
          */
         enum class PolygonMode: GLenum {
             /**
@@ -861,6 +877,8 @@ class MAGNUM_GL_EXPORT Renderer {
             /**
              * Starts of boundary edges are drawn as points. See also
              * @ref setPointSize().
+             * @requires_es_extension Extension @gl_extension{NV,polygon_mode},
+             *      not available with @m_class{m-doc-external} [ANGLE_polygon_mode](https://chromium.googlesource.com/angle/angle/+/HEAD/extensions/ANGLE_polygon_mode.txt)
              */
             #ifndef MAGNUM_TARGET_GLES
             Point = GL_POINT
@@ -874,7 +892,8 @@ class MAGNUM_GL_EXPORT Renderer {
          *
          * Initial value is @ref PolygonMode::Fill.
          * @see @fn_gl_keyword{PolygonMode}
-         * @requires_es_extension Extension @gl_extension{NV,polygon_mode}.
+         * @requires_es_extension Extension @gl_extension{NV,polygon_mode} or
+         *      @m_class{m-doc-external} [ANGLE_polygon_mode](https://chromium.googlesource.com/angle/angle/+/HEAD/extensions/ANGLE_polygon_mode.txt).
          *      Otherwise behaves always like the default. See
          *      @ref Mesh::setPrimitive() for possible workaround.
          * @requires_gles WebGL behaves always like the default. See

src/Magnum/GL/Test/RendererGLTest.cpp

@@ -61,6 +61,9 @@ struct RendererGLTest: OpenGLTester {
 
     void maxLineWidth();
     void pointCoord();
+    #ifndef MAGNUM_TARGET_WEBGL
+    void polygonMode();
+    #endif
     #if !defined(MAGNUM_TARGET_GLES2) && !defined(MAGNUM_TARGET_WEBGL)
     void patchParameters();
     #endif
@@ -86,6 +89,9 @@ using namespace Math::Literals;
 RendererGLTest::RendererGLTest() {
     addTests({&RendererGLTest::maxLineWidth,
               &RendererGLTest::pointCoord,
+              #ifndef MAGNUM_TARGET_WEBGL
+              &RendererGLTest::polygonMode,
+              #endif
               #if !defined(MAGNUM_TARGET_GLES2) && !defined(MAGNUM_TARGET_WEBGL)
               &RendererGLTest::patchParameters,
               #endif
@@ -253,6 +259,22 @@ void RendererGLTest::pointCoord() {
         (DebugTools::CompareImageToFile{_manager, maxThreshold, meanThreshold}));
 }
 
+#ifndef MAGNUM_TARGET_WEBGL
+void RendererGLTest::polygonMode() {
+    #ifdef MAGNUM_TARGET_GLES
+    if(!Context::current().isExtensionSupported<Extensions::NV::polygon_mode>() &&
+       !Context::current().isExtensionSupported<Extensions::ANGLE::polygon_mode>())
+        CORRADE_SKIP("Neither" << Extensions::NV::polygon_mode::string() << "nor" << Extensions::ANGLE::polygon_mode::string() << "is supported.");
+    #endif
+
+    /* Just check for crashes and GL errors, revert back to the default mode to
+       not break other tests */
+    Renderer::setPolygonMode(Renderer::PolygonMode::Line);
+    Renderer::setPolygonMode(Renderer::PolygonMode::Fill);
+    MAGNUM_VERIFY_NO_GL_ERROR();
+}
+#endif
+
 #if !defined(MAGNUM_TARGET_GLES2) && !defined(MAGNUM_TARGET_WEBGL)
 void RendererGLTest::patchParameters() {
     #ifndef MAGNUM_TARGET_GLES