matlab 对3D模型文件的读入与显示函数

function obj_display ( input_file_name ) %*****************************************************************************80 % %% OBJ_DISPLAY displays the faces of a shape defined by an OBJ file. % % Usage: % % obj_display ( 'file.obj' ) % % Licensing: % % This code is distributed under the GNU LGPL license. % % Modified: % % 27 September 2008 % % Author: % % John Burkardt % timestamp ( ); fprintf ( 1, '\n' ); fprintf ( 1, 'OBJ_DISPLAY\n' ); fprintf ( 1, ' MATLAB version\n' ); fprintf ( 1, '\n' ); fprintf ( 1, ' Reads an object in an ASCII OBJ file.\n' ); fprintf ( 1, ' Display it as a MATLAB shape.\n' ); % % If at least one command line argument, it's the input file name. % if ( nargin < 1 ) fprintf ( 1, '\n' ); fprintf ( 1, 'OBJ_DISPLAY:\n' ); input_file_name = input ( 'Enter the name of the input file:' ); end % % Get sizes. % [ node_num, face_num, normal_num, order_max ] = obj_size ( input_file_name ); % % Print the sizes. % obj_size_print ( input_file_name, node_num, face_num, normal_num, order_max ); % % Get the data. % [ node_xyz, face_order, face_node ] = ... obj_read ( input_file_name, node_num, face_num, normal_num, order_max ); % % FACE_NODE may contain polygons of different orders. % To make the call to PATCH, we will assume all the polygons are the same order. % To do so, we'll simply "stutter" the first node in each face list. % for face = 1 : face_num face_node(face_order(face)+1:order_max,face) = face_node(1,face); end % % If any node index is still less than 1, set the whole face to 1's. % We're giving up on this presumably meaningless face, but we need to % do it in a way that keeps MATLAB happy! % for face = 1 : face_num for i = 1 : order_max face_node(i,face) = max ( face_node(i,face), 1 ); end end % % Display the shape. % handle = patch ( 'Vertices', node_xyz', 'Faces', face_node' ); set ( handle, 'FaceColor', [0.5, 0.6, 0.8], 'EdgeColor', 'Black' ); axis equal; grid on; xlabel ( '--X axis--' ) ylabel ( '--Y axis--' ) zlabel ( '--Z axis--' ) % % The TITLE function will interpret underscores in the title. % We need to unescape such escape sequences! % title_string = s_escape_tex ( input_file_name ); title ( title_string ) % % Terminate. % fprintf ( 1, '\n' ); fprintf ( 1, 'OBJ_DISPLAY:\n' ); fprintf ( 1, ' Normal end of execution.\n' ); fprintf ( 1, '\n' ); timestamp ( ); return end function c = ch_cap ( c ) %*****************************************************************************80 % %% CH_CAP capitalizes a single character. % % Licensing: % % This code is distributed under the GNU LGPL license. % % Modified: % % 22 November 2003 % % Author: % % John Burkardt % % Parameters: % % Input, character C, the character to capitalize. % % Output, character C, the capitalized character. % if ( 'a' <= c && c <= 'z' ) c = c + 'A' - 'a'; end return end function truefalse = ch_eqi ( c1, c2 ) %*****************************************************************************80 % %% CH_EQI is a case insensitive comparison of two characters for equality. % % Example: % % CH_EQI ( 'A', 'a' ) is TRUE. % % Licensing: % % This code is distributed under the GNU LGPL license. % % Modified: % % 28 July 2000 % % Author: % % John Burkardt % % Parameters: % % Input, character C1, C2, the characters to compare. % % Output, logical TRUEFALSE, is TRUE (1) if the characters are equal. % FALSE = 0; TRUE = 1; if ( ch_cap ( c1 ) == ch_cap ( c2 ) ) truefalse = TRUE; else truefalse = FALSE; end return end function value = ch_index ( s, c ) %*****************************************************************************80 % %% CH_INDEX is the first occurrence of a character in a string. % % Licensing: % % This code is distributed under the GNU LGPL license. % % Modified: % % 01 May 2004 % % Author: % % John Burkardt % % Parameters: % % Input, string S, the string to be searched. % % Input, character C, the character to be searched for. % % Output, integer VALUE, the location of the first occurrence of C % in the string, or 0 if C does not occur. % value = 0; for i = 1 : length ( s ) if ( s(i:i) == c ) value = i; return end end return end function value = ch_is_control ( ch ) %*****************************************************************************80 % %% CH_IS_CONTROL is TRUE if a character is a control character. % % Discussion: % % A "control character" has ASCII code <= 31 or 127 <= ASCII code. % % Licensing: % % This code is distributed under the GNU LGPL license. % % Modified: % % 27 September 2008 % % Author: % % John Burkardt % % Parameters: % % Input, character CH, the character to be tested. % % Output, integer CH_IS_CONTROL, TRUE if the character is a control % character, and FALSE otherwise. % if ( ch <= 31 || 127 <= ch ) value = 1; else value = 0; end return end function truefalse = ch_is_digit ( c ) %*****************************************************************************80 % % CH_IS_DIGIT returns TRUE if the character C is a digit. % % Licensing: % % This code is distributed under the GNU LGPL license. % % Modified: % % 11 December 2003 % % Author: % % John Burkardt % % Parameters: % % Input, character C, a character. % % Output, integer TRUEFALSE, is TRUE (1) if C is a digit, FALSE (0) otherwise. % TRUE = 1; FALSE = 0; if ( '0' <= c && c <= '9' ) truefalse = TRUE; else truefalse = FALSE; end return end function digit = ch_to_digit ( c ) %*****************************************************************************80 % %% CH_TO_DIGIT returns the integer value of a base 10 digit. % % Example: % % C DIGIT % --- ----- % '0' 0 % '1' 1 % ... ... % '9' 9 % ' ' 0 % 'X' -1 % % Licensing: % % This code is distributed under the GNU LGPL license. % % Modified: % % 22 November 2003 % % Author: % % John Burkardt % % Parameters: % % Input, character C, the decimal digit, '0' through '9' or blank % are legal. % % Output, integer DIGIT, the corresponding integer value. If C was % 'illegal', then DIGIT is -1. % if ( '0' <= c && c <= '9' ) digit = c - '0'; elseif ( c == ' ' ) digit = 0; else digit = -1; end return end function [ node_xyz, face_order, face_node, normal_vector, vertex_normal ] = ... obj_read ( input_file_name, node_num, face_num, normal_num, order_max ) %*****************************************************************************80 % %% OBJ_READ reads graphics information from a Wavefront OBJ file. % % Discussion: % % It is intended that the information read from the file can % either start a whole new graphics object, or simply be added % to a current graphics object via the '<<' command. % % This is controlled by whether the input values have been zeroed % out or not. This routine simply tacks on the information it % finds to the current graphics object. % % Example: % % # magnolia.obj % % v -3.269770 -39.572201 0.876128 % v -3.263720 -39.507999 2.160890 % ... % v 0.000000 -9.988540 0.000000 % vn 1.0 0.0 0.0 % ... % vn 0.0 1.0 0.0 % % f 8 9 11 10 % f 12 13 15 14 % ... % f 788 806 774 % % Licensing: % % This code is distributed under the GNU LGPL license. % % Modified: % % 27 September 2008 % % Author: % % John Burkardt % % Parameters: % %