Support for ARB_texture_stencil8.

src/AbstractTexture.cpp

@@ -423,6 +423,11 @@ ImageFormat AbstractTexture::imageFormatForInternalFormat(const TextureFormat in
         #endif
             return ImageFormat::DepthComponent;
 
+        #ifndef MAGNUM_TARGET_GLES
+        case TextureFormat::StencilIndex8:
+            return ImageFormat::StencilIndex;
+        #endif
+
         case TextureFormat::DepthStencil:
         case TextureFormat::Depth24Stencil8:
         #ifndef MAGNUM_TARGET_GLES2
@@ -605,6 +610,11 @@ ImageType AbstractTexture::imageTypeForInternalFormat(const TextureFormat intern
             return ImageType::Float;
         #endif
 
+        #ifndef MAGNUM_TARGET_GLES
+        case TextureFormat::StencilIndex8:
+            return ImageType::UnsignedByte;
+        #endif
+
         case TextureFormat::DepthStencil:
         case TextureFormat::Depth24Stencil8:
             return ImageType::UnsignedInt248;

src/ImageFormat.h

@@ -223,8 +223,11 @@ enum class ImageFormat: GLenum {
 
     #ifndef MAGNUM_TARGET_GLES3
     /**
-     * Stencil index. For framebuffer reading only.
-     * @requires_es_extension %Extension @es_extension2{NV,read_stencil,GL_NV_read_depth_stencil}
+     * Stencil index.
+     * @requires_gl44 %Extension @extension{ARB,texture_stencil8} for texture
+     *      data, otherwise for framebuffer reading only.
+     * @requires_es_extension %Extension @es_extension2{NV,read_stencil,GL_NV_read_depth_stencil},
+     *      for framebuffer reading only.
      * @todo Where to get GL_STENCIL_INDEX in ES?
      */
     #ifndef MAGNUM_TARGET_GLES

src/TextureFormat.h

@@ -809,6 +809,15 @@ enum class TextureFormat: GLenum {
     DepthComponent32F = GL_DEPTH_COMPONENT32F,
     #endif
 
+    #ifndef MAGNUM_TARGET_GLES
+    /**
+     * Stencil index, 8bit.
+     * @requires_gl44 %Extension @extension{ARB,texture_stencil8}
+     * @requires_gl Only available as renderbuffer format in OpenGL ES.
+     */
+    StencilIndex8 = GL_STENCIL_INDEX8,
+    #endif
+
     /**
      * Depth and stencil component, size implementation-dependent.
      * @deprecated Prefer to use exactly specified version of this format, e.g.