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diff --git a/source/blender/gpu/opengl/gl_framebuffer.hh b/source/blender/gpu/opengl/gl_framebuffer.hh
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+/*
+ * This program is free software; you can redistribute it and/or
+ * modify it under the terms of the GNU General Public License
+ * as published by the Free Software Foundation; either version 2
+ * of the License, or (at your option) any later version.
+ *
+ * This program is distributed in the hope that it will be useful,
+ * but WITHOUT ANY WARRANTY; without even the implied warranty of
+ * MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
+ * GNU General Public License for more details.
+ *
+ * You should have received a copy of the GNU General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 51 Franklin Street, Fifth Floor, Boston, MA 02110-1301, USA.
+ *
+ * The Original Code is Copyright (C) 2020 Blender Foundation.
+ * All rights reserved.
+ */
+
+/** \file
+ * \ingroup gpu
+ *
+ * Encapsulation of Framebuffer states (attached textures, viewport, scissors).
+ */
+
+#pragma once
+
+#include "MEM_guardedalloc.h"
+
+#include "glew-mx.h"
+
+#include "gpu_framebuffer_private.hh"
+
+namespace blender::gpu {
+
+/**
+ * Implementation of FrameBuffer object using OpenGL.
+ **/
+class GLFrameBuffer : public FrameBuffer {
+ private:
+  /** OpenGL handle. */
+  GLuint fbo_id_ = 0;
+  /** Context the handle is from. Framebuffers are not shared accros contexts. */
+  GLContext *context_ = NULL;
+  /** Copy of the GL state. Contains ONLY color attachments enums for slot binding. */
+  GLenum gl_attachments_[GPU_FB_MAX_COLOR_ATTACHMENT];
+  /** Internal framebuffers are immutable. */
+  bool immutable_;
+  /** True is the framebuffer has it's first color target using the GPU_SRGB8_A8 format. */
+  bool srgb_;
+
+ public:
+  /**
+   * Create a conventional framebuffer to attach texture to.
+   **/
+  GLFrameBuffer(const char *name);
+
+  /**
+   * Special Framebuffer encapsulating internal window framebuffer.
+   *  (i.e.: GL_FRONT_LEFT, GL_BACK_RIGHT, ...)
+   * @param ctx     context the handle is from.
+   * @param target  the internal GL name (i.e: GL_BACK_LEFT).
+   * @param fbo     the (optional) already created object for some implementation. Default is 0.
+   * @param w       buffer width.
+   * @param h       buffer height.
+   **/
+  GLFrameBuffer(const char *name, GLContext *ctx, GLenum target, GLuint fbo, int w, int h);
+
+  ~GLFrameBuffer();
+
+  void bind(bool enabled_srgb) override;
+
+  bool check(char err_out[256]) override;
+
+  void clear(eGPUFrameBufferBits buffers,
+             const float clear_col[4],
+             float clear_depth,
+             uint clear_stencil) override;
+  void clear_multi(const float (*clear_cols)[4]) override;
+
+  void read(eGPUFrameBufferBits planes,
+            eGPUDataFormat format,
+            const int area[4],
+            int channel_len,
+            int slot,
+            void *r_data) override;
+
+  void blit_to(eGPUFrameBufferBits planes,
+               int src_slot,
+               FrameBuffer *dst,
+               int dst_slot,
+               int dst_offset_x,
+               int dst_offset_y) override;
+
+ private:
+  void init(void);
+  void update_attachments(void);
+  void update_drawbuffers(void);
+
+  MEM_CXX_CLASS_ALLOC_FUNCS("GLFrameBuffer");
+};
+
+/* -------------------------------------------------------------------- */
+/** \name Enums Conversion
+ * \{ */
+
+static inline GLenum to_gl(const GPUAttachmentType type)
+{
+#define ATTACHMENT(X) \
+  case GPU_FB_##X: { \
+    return GL_##X; \
+  } \
+    ((void)0)
+
+  switch (type) {
+    ATTACHMENT(DEPTH_ATTACHMENT);
+    ATTACHMENT(DEPTH_STENCIL_ATTACHMENT);
+    ATTACHMENT(COLOR_ATTACHMENT0);
+    ATTACHMENT(COLOR_ATTACHMENT1);
+    ATTACHMENT(COLOR_ATTACHMENT2);
+    ATTACHMENT(COLOR_ATTACHMENT3);
+    ATTACHMENT(COLOR_ATTACHMENT4);
+    ATTACHMENT(COLOR_ATTACHMENT5);
+    default:
+      BLI_assert(0);
+      return GL_COLOR_ATTACHMENT0;
+  }
+#undef ATTACHMENT
+}
+
+static inline GLbitfield to_gl(const eGPUFrameBufferBits bits)
+{
+  GLbitfield mask = 0;
+  mask |= (bits & GPU_DEPTH_BIT) ? GL_DEPTH_BUFFER_BIT : 0;
+  mask |= (bits & GPU_STENCIL_BIT) ? GL_STENCIL_BUFFER_BIT : 0;
+  mask |= (bits & GPU_COLOR_BIT) ? GL_COLOR_BUFFER_BIT : 0;
+  return mask;
+}
+
+/** \} */
+
+}  // namespace blender::gpu