1 files changed, 102 insertions, 0 deletions
diff --git a/source/blender/gpu/GPU_element.h b/source/blender/gpu/GPU_element.h
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+++ b/source/blender/gpu/GPU_element.h
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+/*
+ * ***** BEGIN GPL LICENSE BLOCK *****
+ *
+ * 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.
+ *
+ * Contributor(s): Blender Foundation
+ *
+ * ***** END GPL LICENSE BLOCK *****
+ */
+
+/** \file blender/gpu/gwn_element.h
+ *  \ingroup gpu
+ *
+ * Gawain element list (AKA index buffer)
+ */
+
+#ifndef __GWN_ELEMENT_H__
+#define __GWN_ELEMENT_H__
+
+#include "GPU_primitive.h"
+
+#define GWN_TRACK_INDEX_RANGE 1
+
+#define GWN_PRIM_RESTART 0xFFFFFFFF
+
+typedef enum {
+	GWN_INDEX_U8, /* GL has this, Vulkan does not */
+	GWN_INDEX_U16,
+	GWN_INDEX_U32
+} Gwn_IndexBufType;
+
+typedef struct Gwn_IndexBuf {
+	uint index_len;
+#if GWN_TRACK_INDEX_RANGE
+	Gwn_IndexBufType index_type;
+	uint32_t gl_index_type;
+	uint min_index;
+	uint max_index;
+	uint base_index;
+#endif
+	uint32_t vbo_id; /* 0 indicates not yet sent to VRAM */
+	bool use_prim_restart;
+} Gwn_IndexBuf;
+
+void GWN_indexbuf_use(Gwn_IndexBuf*);
+uint GWN_indexbuf_size_get(const Gwn_IndexBuf*);
+
+typedef struct Gwn_IndexBufBuilder {
+	uint max_allowed_index;
+	uint max_index_len;
+	uint index_len;
+	Gwn_PrimType prim_type;
+	uint* data;
+	bool use_prim_restart;
+} Gwn_IndexBufBuilder;
+
+
+/* supports all primitive types. */
+void GWN_indexbuf_init_ex(Gwn_IndexBufBuilder*, Gwn_PrimType, uint index_len, uint vertex_len, bool use_prim_restart);
+
+/* supports only GWN_PRIM_POINTS, GWN_PRIM_LINES and GWN_PRIM_TRIS. */
+void GWN_indexbuf_init(Gwn_IndexBufBuilder*, Gwn_PrimType, uint prim_len, uint vertex_len);
+
+void GWN_indexbuf_add_generic_vert(Gwn_IndexBufBuilder*, uint v);
+void GWN_indexbuf_add_primitive_restart(Gwn_IndexBufBuilder*);
+
+void GWN_indexbuf_add_point_vert(Gwn_IndexBufBuilder*, uint v);
+void GWN_indexbuf_add_line_verts(Gwn_IndexBufBuilder*, uint v1, uint v2);
+void GWN_indexbuf_add_tri_verts(Gwn_IndexBufBuilder*, uint v1, uint v2, uint v3);
+void GWN_indexbuf_add_line_adj_verts(Gwn_IndexBufBuilder*, uint v1, uint v2, uint v3, uint v4);
+
+Gwn_IndexBuf* GWN_indexbuf_build(Gwn_IndexBufBuilder*);
+void GWN_indexbuf_build_in_place(Gwn_IndexBufBuilder*, Gwn_IndexBuf*);
+
+void GWN_indexbuf_discard(Gwn_IndexBuf*);
+
+
+/* Macros */
+
+#define GWN_INDEXBUF_DISCARD_SAFE(elem) do { \
+	if (elem != NULL) { \
+		GWN_indexbuf_discard(elem); \
+		elem = NULL; \
+	} \
+} while (0)
+
+#endif /* __GWN_ELEMENT_H__ */