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diff --git a/intern/gawain/gawain/gwn_batch.h b/intern/gawain/gawain/gwn_batch.h
new file mode 100644
index 00000000000..ee1599845c8
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+++ b/intern/gawain/gawain/gwn_batch.h
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+
+// Gawain geometry batch
+//
+// This code is part of the Gawain library, with modifications
+// specific to integration with Blender.
+//
+// Copyright 2016 Mike Erwin
+//
+// This Source Code Form is subject to the terms of the Mozilla Public License, v. 2.0. If a copy of
+// the MPL was not distributed with this file, You can obtain one at https://mozilla.org/MPL/2.0/.
+
+#pragma once
+
+#include "gwn_vertex_buffer.h"
+#include "gwn_element.h"
+#include "gwn_shader_interface.h"
+
+typedef enum {
+	GWN_BATCH_READY_TO_FORMAT,
+	GWN_BATCH_READY_TO_BUILD,
+	GWN_BATCH_BUILDING,
+	GWN_BATCH_READY_TO_DRAW
+} Gwn_BatchPhase;
+
+#define GWN_BATCH_VBO_MAX_LEN 3
+
+typedef struct Gwn_Batch {
+	// geometry
+	Gwn_VertBuf* verts[GWN_BATCH_VBO_MAX_LEN]; // verts[0] is required, others can be NULL
+	Gwn_IndexBuf* elem; // NULL if element list not needed
+	Gwn_PrimType prim_type;
+	GLenum gl_prim_type;
+
+	// book-keeping
+	GLuint vao_id; // remembers all geometry state (vertex attrib bindings & element buffer)
+	Gwn_BatchPhase phase;
+	bool program_dirty;
+	bool program_in_use;
+	unsigned owns_flag;
+
+	// state
+	GLuint program;
+	const Gwn_ShaderInterface* interface;
+} Gwn_Batch;
+
+enum {
+	GWN_BATCH_OWNS_VBO = (1 << 0),
+	/* each vbo index gets bit-shifted */
+	GWN_BATCH_OWNS_INDEX = (1 << 31),
+};
+
+Gwn_Batch* GWN_batch_create_ex(Gwn_PrimType, Gwn_VertBuf*, Gwn_IndexBuf*, unsigned owns_flag);
+void GWN_batch_init_ex(Gwn_Batch*, Gwn_PrimType, Gwn_VertBuf*, Gwn_IndexBuf*, unsigned owns_flag);
+
+#define GWN_batch_create(prim, verts, elem) \
+	GWN_batch_create_ex(prim, verts, elem, 0)
+#define GWN_batch_init(batch, prim, verts, elem) \
+	GWN_batch_init_ex(batch, prim, verts, elem, 0)
+
+void GWN_batch_discard(Gwn_Batch*); // verts & elem are not discarded
+
+int GWN_batch_vertbuf_add_ex(Gwn_Batch*, Gwn_VertBuf*, bool own_vbo);
+
+#define GWN_batch_vertbuf_add(batch, verts) \
+	GWN_batch_vertbuf_add_ex(batch, verts, false)
+
+void GWN_batch_program_set(Gwn_Batch*, GLuint program, const Gwn_ShaderInterface*);
+void GWN_batch_program_unset(Gwn_Batch*);
+// Entire batch draws with one shader program, but can be redrawn later with another program.
+// Vertex shader's inputs must be compatible with the batch's vertex format.
+
+void GWN_batch_program_use_begin(Gwn_Batch*); // call before Batch_Uniform (temp hack?)
+void GWN_batch_program_use_end(Gwn_Batch*);
+
+void GWN_batch_uniform_1i(Gwn_Batch*, const char* name, int value);
+void GWN_batch_uniform_1b(Gwn_Batch*, const char* name, bool value);
+void GWN_batch_uniform_1f(Gwn_Batch*, const char* name, float value);
+void GWN_batch_uniform_2f(Gwn_Batch*, const char* name, float x, float y);
+void GWN_batch_uniform_3f(Gwn_Batch*, const char* name, float x, float y, float z);
+void GWN_batch_uniform_4f(Gwn_Batch*, const char* name, float x, float y, float z, float w);
+void GWN_batch_uniform_2fv(Gwn_Batch*, const char* name, const float data[2]);
+void GWN_batch_uniform_3fv(Gwn_Batch*, const char* name, const float data[3]);
+void GWN_batch_uniform_4fv(Gwn_Batch*, const char* name, const float data[4]);
+
+void GWN_batch_draw(Gwn_Batch*);
+
+
+// clement : temp stuff
+void GWN_batch_draw_stupid(Gwn_Batch*);
+void GWN_batch_draw_stupid_instanced(Gwn_Batch*, unsigned int instance_vbo, int instance_count,
+                                 int attrib_nbr, int attrib_stride, int attrib_loc[16], int attrib_size[16]);
+void GWN_batch_draw_stupid_instanced_with_batch(Gwn_Batch*, Gwn_Batch*);
+
+
+
+
+
+#if 0 // future plans
+
+// Can multiple batches share a Gwn_VertBuf? Use ref count?
+
+
+// We often need a batch with its own data, to be created and discarded together.
+// WithOwn variants reduce number of system allocations.
+
+typedef struct BatchWithOwnVertexBuffer {
+	Gwn_Batch batch;
+	Gwn_VertBuf verts; // link batch.verts to this
+} BatchWithOwnVertexBuffer;
+
+typedef struct BatchWithOwnElementList {
+	Gwn_Batch batch;
+	Gwn_IndexBuf elem; // link batch.elem to this
+} BatchWithOwnElementList;
+
+typedef struct BatchWithOwnVertexBufferAndElementList {
+	Gwn_Batch batch;
+	Gwn_IndexBuf elem; // link batch.elem to this
+	Gwn_VertBuf verts; // link batch.verts to this
+} BatchWithOwnVertexBufferAndElementList;
+
+Gwn_Batch* create_BatchWithOwnVertexBuffer(Gwn_PrimType, Gwn_VertFormat*, unsigned v_ct, Gwn_IndexBuf*);
+Gwn_Batch* create_BatchWithOwnElementList(Gwn_PrimType, Gwn_VertBuf*, unsigned prim_ct);
+Gwn_Batch* create_BatchWithOwnVertexBufferAndElementList(Gwn_PrimType, Gwn_VertFormat*, unsigned v_ct, unsigned prim_ct);
+// verts: shared, own
+// elem: none, shared, own
+Gwn_Batch* create_BatchInGeneral(Gwn_PrimType, VertexBufferStuff, ElementListStuff);
+
+#endif // future plans
+
+
+/* Macros */
+
+#define GWN_BATCH_DISCARD_SAFE(batch) do { \
+	if (batch != NULL) { \
+		GWN_batch_discard(batch); \
+		batch = NULL; \
+	} \
+} while (0)