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diff --git a/source/blender/draw/engines/image/image_space.hh b/source/blender/draw/engines/image/image_space.hh
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+++ b/source/blender/draw/engines/image/image_space.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.
+ *
+ * Copyright 2021, Blender Foundation.
+ */
+
+/** \file
+ * \ingroup draw_engine
+ */
+
+#pragma once
+
+class ShaderParameters;
+
+/**
+ *  Space accessor.
+ *
+ *  Image engine is used to draw the images inside multiple spaces \see SpaceLink.
+ *  The AbstractSpaceAccessor is an interface to communicate with a space.
+ */
+class AbstractSpaceAccessor {
+ public:
+  virtual ~AbstractSpaceAccessor() = default;
+
+  /**
+   * Return the active image of the space.
+   *
+   * The returned image will be drawn in the space.
+   *
+   * The return value is optional.
+   */
+  virtual Image *get_image(Main *bmain) = 0;
+
+  /**
+   * Return the #ImageUser of the space.
+   *
+   * The return value is optional.
+   */
+  virtual ImageUser *get_image_user() = 0;
+
+  /**
+   * Acquire the image buffer of the image.
+   *
+   * \param image: Image to get the buffer from. Image is the same as returned from the #get_image
+   * member.
+   * \param lock: pointer to a lock object.
+   * \return Image buffer of the given image.
+   */
+  virtual ImBuf *acquire_image_buffer(Image *image, void **lock) = 0;
+
+  /**
+   * Release a previous locked image from #acquire_image_buffer.
+   */
+  virtual void release_buffer(Image *image, ImBuf *image_buffer, void *lock) = 0;
+
+  /**
+   * Update the r_shader_parameters with space specific settings.
+   *
+   * Only update the #ShaderParameters.flags and #ShaderParameters.shuffle. Other parameters
+   * are updated inside the image engine.
+   */
+  virtual void get_shader_parameters(ShaderParameters &r_shader_parameters,
+                                     ImBuf *image_buffer,
+                                     bool is_tiled) = 0;
+
+  /**
+   * Retrieve the gpu textures to draw.
+   */
+  virtual void get_gpu_textures(Image *image,
+                                ImageUser *iuser,
+                                ImBuf *image_buffer,
+                                GPUTexture **r_gpu_texture,
+                                bool *r_owns_texture,
+                                GPUTexture **r_tex_tile_data) = 0;
+
+  /** \brief Is (wrap) repeat option enabled in the space. */
+  virtual bool use_tile_drawing() const = 0;
+
+  /**
+   * \brief Initialize r_uv_to_texture matrix to transform from normalized screen space coordinates
+   * (0..1) to texture space UV coordinates.
+   */
+  virtual void init_ss_to_texture_matrix(const ARegion *region,
+                                         const float image_resolution[2],
+                                         float r_uv_to_texture[4][4]) const = 0;
+
+};  // namespace blender::draw::image_engine