1 files changed, 81 insertions, 0 deletions
diff --git a/source/blender/gpu/opengl/gl_immediate.hh b/source/blender/gpu/opengl/gl_immediate.hh
new file mode 100644
index 00000000000..2b9b90d692b
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+++ b/source/blender/gpu/opengl/gl_immediate.hh
@@ -0,0 +1,81 @@
+/*
+ * 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) 2016 by Mike Erwin.
+ * All rights reserved.
+ */
+
+/** \file
+ * \ingroup gpu
+ *
+ * Mimics old style opengl immediate mode drawing.
+ */
+
+#pragma once
+
+#include "MEM_guardedalloc.h"
+
+#include "glew-mx.h"
+
+#include "gpu_immediate_private.hh"
+
+namespace blender::gpu {
+
+/* size of internal buffer */
+#define DEFAULT_INTERNAL_BUFFER_SIZE (4 * 1024 * 1024)
+
+class GLImmediate : public Immediate {
+ private:
+  /* Use two buffers for strict and unstrict vertex count to
+   * avoid some huge driver slowdown (see T70922).
+   * Use accessor functions to get / modify. */
+  struct {
+    /** Opengl Handle for this buffer. */
+    GLuint vbo_id = 0;
+    /** Offset of the mapped data in data. */
+    size_t buffer_offset = 0;
+    /** Size of the whole buffer in bytes. */
+    size_t buffer_size = 0;
+  } buffer, buffer_strict;
+  /** Size in bytes of the mapped region. */
+  size_t bytes_mapped_ = 0;
+  /** Vertex array for this immediate mode instance. */
+  GLuint vao_id_ = 0;
+
+ public:
+  GLImmediate();
+  ~GLImmediate();
+
+  uchar *begin(void) override;
+  void end(void) override;
+
+ private:
+  GLuint &vbo_id(void)
+  {
+    return strict_vertex_len ? buffer_strict.vbo_id : buffer.vbo_id;
+  };
+
+  size_t &buffer_offset(void)
+  {
+    return strict_vertex_len ? buffer_strict.buffer_offset : buffer.buffer_offset;
+  };
+
+  size_t &buffer_size(void)
+  {
+    return strict_vertex_len ? buffer_strict.buffer_size : buffer.buffer_size;
+  };
+};
+
+}  // namespace blender::gpu
+\ No newline at end of file