--- /dev/null
+/*
+ * The 3D Studio File Format Library
+ * Copyright (C) 1996-2001 by J.E. Hoffmann <je-h@gmx.net>
+ * All rights reserved.
+ *
+ * This program is free software; you can redistribute it and/or modify it
+ * under the terms of the GNU Lesser General Public License as published by
+ * the Free Software Foundation; either version 2.1 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 Lesser General Public
+ * License for more details.
+ *
+ * You should have received a copy of the GNU Lesser General Public License
+ * along with this program; if not, write to the Free Software Foundation,
+ * Inc., 675 Mass Ave, Cambridge, MA 02139, USA.
+ *
+ * $Id: background.c,v 1.8 2001/07/07 19:05:30 jeh Exp $
+ */
+#define LIB3DS_EXPORT
+#include <lib3ds/background.h>
+#include <lib3ds/chunk.h>
+#include <lib3ds/io.h>
+#include <string.h>
+#include <math.h>
+
+
+/*!
+ * \defgroup background Background Settings
+ *
+ * \author J.E. Hoffmann <je-h@gmx.net>
+ */
+
+
+static Lib3dsBool
+solid_bgnd_read(Lib3dsBackground *background, Lib3dsIo *io)
+{
+ Lib3dsChunk c;
+ Lib3dsWord chunk;
+
+ if (!lib3ds_chunk_read_start(&c, LIB3DS_SOLID_BGND, io)) {
+ return(LIB3DS_FALSE);
+ }
+
+ while ((chunk=lib3ds_chunk_read_next(&c, io))!=0) {
+ switch (chunk) {
+ case LIB3DS_LIN_COLOR_F:
+ lib3ds_io_read_rgb(io, background->solid.col);
+ break;
+ case LIB3DS_COLOR_F:
+ lib3ds_io_read_rgb(io, background->solid.col);
+ break;
+ default:
+ lib3ds_chunk_unknown(chunk);
+ }
+ }
+
+ lib3ds_chunk_read_end(&c, io);
+ return(LIB3DS_TRUE);
+}
+
+
+static Lib3dsBool
+v_gradient_read(Lib3dsBackground *background, Lib3dsIo *io)
+{
+ Lib3dsChunk c;
+ Lib3dsWord chunk;
+ int index[2];
+ Lib3dsRgb col[2][3];
+ int have_lin=0;
+
+
+ if (!lib3ds_chunk_read_start(&c, LIB3DS_V_GRADIENT, io)) {
+ return(LIB3DS_FALSE);
+ }
+ background->gradient.percent=lib3ds_io_read_float(io);
+ lib3ds_chunk_read_tell(&c, io);
+
+ index[0]=index[1]=0;
+ while ((chunk=lib3ds_chunk_read_next(&c, io))!=0) {
+ switch (chunk) {
+ case LIB3DS_COLOR_F:
+ lib3ds_io_read_rgb(io, col[0][index[0]]);
+ index[0]++;
+ break;
+ case LIB3DS_LIN_COLOR_F:
+ lib3ds_io_read_rgb(io, col[1][index[1]]);
+ index[1]++;
+ have_lin=1;
+ break;
+ default:
+ lib3ds_chunk_unknown(chunk);
+ }
+ }
+ {
+ int i;
+ for (i=0; i<3; ++i) {
+ background->gradient.top[i]=col[have_lin][0][i];
+ background->gradient.middle[i]=col[have_lin][1][i];
+ background->gradient.bottom[i]=col[have_lin][2][i];
+ }
+ }
+ lib3ds_chunk_read_end(&c, io);
+ return(LIB3DS_TRUE);
+}
+
+
+/*!
+ * \ingroup background
+ */
+Lib3dsBool
+lib3ds_background_read(Lib3dsBackground *background, Lib3dsIo *io)
+{
+ Lib3dsChunk c;
+
+ if (!lib3ds_chunk_read(&c, io)) {
+ return(LIB3DS_FALSE);
+ }
+
+ switch (c.chunk) {
+ case LIB3DS_BIT_MAP:
+ {
+ if (!lib3ds_io_read_string(io, background->bitmap.name, 64)) {
+ return(LIB3DS_FALSE);
+ }
+ }
+ break;
+ case LIB3DS_SOLID_BGND:
+ {
+ lib3ds_chunk_read_reset(&c, io);
+ if (!solid_bgnd_read(background, io)) {
+ return(LIB3DS_FALSE);
+ }
+ }
+ break;
+ case LIB3DS_V_GRADIENT:
+ {
+ lib3ds_chunk_read_reset(&c, io);
+ if (!v_gradient_read(background, io)) {
+ return(LIB3DS_FALSE);
+ }
+ }
+ break;
+ case LIB3DS_USE_BIT_MAP:
+ {
+ background->bitmap.use=LIB3DS_TRUE;
+ }
+ break;
+ case LIB3DS_USE_SOLID_BGND:
+ {
+ background->solid.use=LIB3DS_TRUE;
+ }
+ break;
+ case LIB3DS_USE_V_GRADIENT:
+ {
+ background->gradient.use=LIB3DS_TRUE;
+ }
+ break;
+ }
+
+ return(LIB3DS_TRUE);
+}
+
+
+static Lib3dsBool
+colorf_write(Lib3dsRgba rgb, Lib3dsIo *io)
+{
+ Lib3dsChunk c;
+
+ c.chunk=LIB3DS_COLOR_F;
+ c.size=18;
+ lib3ds_chunk_write(&c,io);
+ lib3ds_io_write_rgb(io, rgb);
+
+ c.chunk=LIB3DS_LIN_COLOR_F;
+ c.size=18;
+ lib3ds_chunk_write(&c,io);
+ lib3ds_io_write_rgb(io, rgb);
+ return(LIB3DS_TRUE);
+}
+
+
+static Lib3dsBool
+colorf_defined(Lib3dsRgba rgb)
+{
+ int i;
+ for (i=0; i<3; ++i) {
+ if (fabs(rgb[i])>LIB3DS_EPSILON) {
+ break;
+ }
+ }
+ return(i<3);
+}
+
+
+/*!
+ * \ingroup background
+ */
+Lib3dsBool
+lib3ds_background_write(Lib3dsBackground *background, Lib3dsIo *io)
+{
+ if (strlen(background->bitmap.name)) { /*---- LIB3DS_BIT_MAP ----*/
+ Lib3dsChunk c;
+ c.chunk=LIB3DS_BIT_MAP;
+ c.size=6+1+strlen(background->bitmap.name);
+ lib3ds_chunk_write(&c,io);
+ lib3ds_io_write_string(io, background->bitmap.name);
+ }
+
+ if (colorf_defined(background->solid.col)) { /*---- LIB3DS_SOLID_BGND ----*/
+ Lib3dsChunk c;
+ c.chunk=LIB3DS_SOLID_BGND;
+ c.size=42;
+ lib3ds_chunk_write(&c,io);
+ colorf_write(background->solid.col, io);
+ }
+
+ if (colorf_defined(background->gradient.top) ||
+ colorf_defined(background->gradient.middle) ||
+ colorf_defined(background->gradient.bottom)) { /*---- LIB3DS_V_GRADIENT ----*/
+ Lib3dsChunk c;
+ c.chunk=LIB3DS_V_GRADIENT;
+ c.size=118;
+ lib3ds_chunk_write(&c,io);
+ lib3ds_io_write_float(io, background->gradient.percent);
+ colorf_write(background->gradient.top,io);
+ colorf_write(background->gradient.middle,io);
+ colorf_write(background->gradient.bottom,io);
+ }
+
+ if (background->bitmap.use) { /*---- LIB3DS_USE_BIT_MAP ----*/
+ Lib3dsChunk c;
+ c.chunk=LIB3DS_USE_BIT_MAP;
+ c.size=6;
+ lib3ds_chunk_write(&c,io);
+ }
+
+ if (background->solid.use) { /*---- LIB3DS_USE_SOLID_BGND ----*/
+ Lib3dsChunk c;
+ c.chunk=LIB3DS_USE_SOLID_BGND;
+ c.size=6;
+ lib3ds_chunk_write(&c,io);
+ }
+
+ if (background->gradient.use) { /*---- LIB3DS_USE_V_GRADIENT ----*/
+ Lib3dsChunk c;
+ c.chunk=LIB3DS_USE_V_GRADIENT;
+ c.size=6;
+ lib3ds_chunk_write(&c,io);
+ }
+
+ return(LIB3DS_TRUE);
+}
+
+
+/*!
+
+\typedef Lib3dsBackground
+ \ingroup background
+ \sa _Lib3dsBackground
+
+*/