[Bf-blender-cvs] [ae6cc4a21db] blender2.8: GPU_batch_presets: move static vars into struct

[Campbell Barton]

Commit: ae6cc4a21db52cfaca5898a4f98a6eb8def2e65a
Author: Campbell Barton
Date:   Mon Jan 15 16:52:28 2018 +1100
Branches: blender2.8
https://developer.blender.org/rBae6cc4a21db52cfaca5898a4f98a6eb8def2e65a

GPU_batch_presets: move static vars into struct

Also use GWN raw stepping API to fill in data.

===================================================================

A	source/blender/gpu/intern/gpu_batch_presets.c

===================================================================

diff --git a/source/blender/gpu/intern/gpu_batch_presets.c b/source/blender/gpu/intern/gpu_batch_presets.c
new file mode 100644
index 00000000000..9db04832a51
--- /dev/null
+++ b/source/blender/gpu/intern/gpu_batch_presets.c
@@ -0,0 +1,200 @@
+/*
+ * ***** 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 Blender Foundation.
+ * All rights reserved.
+ *
+ * The Original Code is: all of this file.
+ *
+ * Contributor(s): Mike Erwin
+ *
+ * ***** END GPL LICENSE BLOCK *****
+ */
+
+/** \file blender/gpu/intern/gpu_batch_presets.c
+ *  \ingroup gpu
+ */
+
+#include "BLI_utildefines.h"
+#include "BLI_math.h"
+
+#include "GPU_batch.h"
+#include "gpu_shader_private.h"
+
+/* Struct to store 3D Batches and their format */
+static struct {
+	struct {
+		Gwn_Batch *sphere_high;
+		Gwn_Batch *sphere_med;
+		Gwn_Batch *sphere_low;
+		Gwn_Batch *sphere_wire_low;
+		Gwn_Batch *sphere_wire_med;
+	} batch;
+
+	Gwn_VertFormat format;
+
+	struct {
+		uint pos, nor;
+	} attr_id;
+} g_presets_3d = {0};
+
+/* We may want 2D presets later. */
+
+/* -------------------------------------------------------------------- */
+/** \name 3D Primitives
+ * \{ */
+
+static void batch_sphere_lat_lon_vert(
+        Gwn_VertBufRaw *pos_step, Gwn_VertBufRaw *nor_step,
+        float lat, float lon)
+{
+	float pos[3];
+	pos[0] = sinf(lat) * cosf(lon);
+	pos[1] = cosf(lat);
+	pos[2] = sinf(lat) * sinf(lon);
+	copy_v3_v3(GWN_vertbuf_raw_step(pos_step), pos);
+	copy_v3_v3(GWN_vertbuf_raw_step(nor_step), pos);
+}
+
+/* Replacement for gluSphere */
+static Gwn_Batch *batch_sphere(int lat_res, int lon_res)
+{
+	const float lon_inc = 2 * M_PI / lon_res;
+	const float lat_inc = M_PI / lat_res;
+	float lon, lat;
+
+	Gwn_VertBuf *vbo = GWN_vertbuf_create_with_format(&g_presets_3d.format);
+	const uint vbo_len = (lat_res - 1) * lon_res * 6;
+	GWN_vertbuf_data_alloc(vbo, vbo_len);
+
+	Gwn_VertBufRaw pos_step, nor_step;
+	GWN_vertbuf_attr_get_raw_data(vbo, g_presets_3d.attr_id.pos, &pos_step);
+	GWN_vertbuf_attr_get_raw_data(vbo, g_presets_3d.attr_id.nor, &nor_step);
+
+	lon = 0.0f;
+	for (int i = 0; i < lon_res; i++, lon += lon_inc) {
+		lat = 0.0f;
+		for (int j = 0; j < lat_res; j++, lat += lat_inc) {
+			if (j != lat_res - 1) { /* Pole */
+				batch_sphere_lat_lon_vert(&pos_step, &nor_step, lat + lat_inc, lon + lon_inc);
+				batch_sphere_lat_lon_vert(&pos_step, &nor_step, lat + lat_inc, lon);
+				batch_sphere_lat_lon_vert(&pos_step, &nor_step, lat,           lon);
+			}
+
+			if (j != 0) { /* Pole */
+				batch_sphere_lat_lon_vert(&pos_step, &nor_step, lat,           lon + lon_inc);
+				batch_sphere_lat_lon_vert(&pos_step, &nor_step, lat + lat_inc, lon + lon_inc);
+				batch_sphere_lat_lon_vert(&pos_step, &nor_step, lat,           lon);
+			}
+		}
+	}
+
+	BLI_assert(vbo_len == GWN_vertbuf_raw_used(&pos_step));
+	BLI_assert(vbo_len == GWN_vertbuf_raw_used(&nor_step));
+
+	return GWN_batch_create_ex(GWN_PRIM_TRIS, vbo, NULL, GWN_BATCH_OWNS_VBO);
+}
+
+static Gwn_Batch *batch_sphere_wire(int lat_res, int lon_res)
+{
+	const float lon_inc = 2 * M_PI / lon_res;
+	const float lat_inc = M_PI / lat_res;
+	float lon, lat;
+
+	Gwn_VertBuf *vbo = GWN_vertbuf_create_with_format(&g_presets_3d.format);
+	const uint vbo_len = (lat_res * lon_res * 2) + ((lat_res - 1) * lon_res * 2);
+	GWN_vertbuf_data_alloc(vbo, vbo_len);
+
+	Gwn_VertBufRaw pos_step, nor_step;
+	GWN_vertbuf_attr_get_raw_data(vbo, g_presets_3d.attr_id.pos, &pos_step);
+	GWN_vertbuf_attr_get_raw_data(vbo, g_presets_3d.attr_id.nor, &nor_step);
+
+	lon = 0.0f;
+	for (int i = 0; i < lon_res; i++, lon += lon_inc) {
+		lat = 0.0f;
+		for (int j = 0; j < lat_res; j++, lat += lat_inc) {
+			batch_sphere_lat_lon_vert(&pos_step, &nor_step, lat + lat_inc, lon);
+			batch_sphere_lat_lon_vert(&pos_step, &nor_step, lat,           lon);
+
+			if (j != lat_res - 1) { /* Pole */
+				batch_sphere_lat_lon_vert(&pos_step, &nor_step, lat + lat_inc, lon + lon_inc);
+				batch_sphere_lat_lon_vert(&pos_step, &nor_step, lat + lat_inc, lon);
+			}
+		}
+	}
+
+	BLI_assert(vbo_len == GWN_vertbuf_raw_used(&pos_step));
+	BLI_assert(vbo_len == GWN_vertbuf_raw_used(&nor_step));
+
+	return GWN_batch_create_ex(GWN_PRIM_LINES, vbo, NULL, GWN_BATCH_OWNS_VBO);
+}
+
+Gwn_Batch *GPU_batch_preset_sphere(int lod)
+{
+	BLI_assert(lod >= 0 && lod <= 2);
+
+	if (lod == 0) {
+		return g_presets_3d.batch.sphere_low;
+	}
+	else if (lod == 1) {
+		return g_presets_3d.batch.sphere_med;
+	}
+	else {
+		return g_presets_3d.batch.sphere_high;
+	}
+}
+
+Gwn_Batch *GPU_batch_preset_sphere_wire(int lod)
+{
+	BLI_assert(lod >= 0 && lod <= 1);
+
+	if (lod == 0) {
+		return g_presets_3d.batch.sphere_wire_low;
+	}
+	else {
+		return g_presets_3d.batch.sphere_wire_med;
+	}
+}
+
+/** \} */
+
+
+void gpu_batch_presets_init(void)
+{
+	if (g_presets_3d.format.attrib_ct == 0) {
+		Gwn_VertFormat *format = &g_presets_3d.format;
+		g_presets_3d.attr_id.pos = GWN_vertformat_attr_add(format, "pos", GWN_COMP_F32, 3, GWN_FETCH_FLOAT);
+		g_presets_3d.attr_id.nor = GWN_vertformat_attr_add(format, "nor", GWN_COMP_F32, 3, GWN_FETCH_FLOAT);
+	}
+
+	/* Hard coded resolution */
+	g_presets_3d.batch.sphere_low = batch_sphere(8, 16);
+	g_presets_3d.batch.sphere_med = batch_sphere(16, 10);
+	g_presets_3d.batch.sphere_high = batch_sphere(32, 24);
+
+	g_presets_3d.batch.sphere_wire_low = batch_sphere_wire(6, 8);
+	g_presets_3d.batch.sphere_wire_med = batch_sphere_wire(8, 16);
+}
+
+void gpu_batch_presets_exit(void)
+{
+	GWN_batch_discard(g_presets_3d.batch.sphere_low);
+	GWN_batch_discard(g_presets_3d.batch.sphere_med);
+	GWN_batch_discard(g_presets_3d.batch.sphere_high);
+	GWN_batch_discard(g_presets_3d.batch.sphere_wire_low);
+	GWN_batch_discard(g_presets_3d.batch.sphere_wire_med);
+}