00001 // Filename: movieVideoCursor.I 00002 // Created by: jyelon (02Jul07) 00003 // 00004 //////////////////////////////////////////////////////////////////// 00005 // 00006 // PANDA 3D SOFTWARE 00007 // Copyright (c) Carnegie Mellon University. All rights reserved. 00008 // 00009 // All use of this software is subject to the terms of the revised BSD 00010 // license. You should have received a copy of this license along 00011 // with this source code in a file named "LICENSE." 00012 // 00013 //////////////////////////////////////////////////////////////////// 00014 00015 //////////////////////////////////////////////////////////////////// 00016 // Function: MovieVideoCursor::get_source 00017 // Access: Published 00018 // Description: Get the MovieVideo which this cursor references. 00019 //////////////////////////////////////////////////////////////////// 00020 INLINE PT(MovieVideo) MovieVideoCursor:: 00021 get_source() const { 00022 return _source; 00023 } 00024 00025 //////////////////////////////////////////////////////////////////// 00026 // Function: MovieVideoCursor::size_x 00027 // Access: Published 00028 // Description: Get the horizontal size of the movie. 00029 //////////////////////////////////////////////////////////////////// 00030 INLINE int MovieVideoCursor:: 00031 size_x() const { 00032 return _size_x; 00033 } 00034 00035 //////////////////////////////////////////////////////////////////// 00036 // Function: MovieVideoCursor::size_y 00037 // Access: Published 00038 // Description: Get the vertical size of the movie. 00039 //////////////////////////////////////////////////////////////////// 00040 INLINE int MovieVideoCursor:: 00041 size_y() const { 00042 return _size_y; 00043 } 00044 00045 //////////////////////////////////////////////////////////////////// 00046 // Function: MovieVideoCursor::get_num_components 00047 // Access: Published 00048 // Description: Returns 4 if the movie has an alpha 00049 // channel, 3 otherwise. 00050 //////////////////////////////////////////////////////////////////// 00051 INLINE int MovieVideoCursor:: 00052 get_num_components() const { 00053 return _num_components; 00054 } 00055 00056 //////////////////////////////////////////////////////////////////// 00057 // Function: MovieVideoCursor::length 00058 // Access: Published 00059 // Description: Returns the length of the movie. 00060 // 00061 // Some kinds of Movie, such as internet TV station, 00062 // might not have a predictable length. In that case, 00063 // the length will be set to a very large number: 1.0E10. 00064 // If the internet TV station goes offline, the video 00065 // or audio stream will set its abort flag. Reaching the 00066 // end of the movie (ie, the specified length) normally 00067 // does not cause the abort flag to be set. 00068 // 00069 // The video and audio streams produced by get_video and 00070 // get_audio are always of unlimited duration - you can 00071 // always read another video frame or another audio 00072 // sample. This is true even if the specified length 00073 // is reached, or an abort is flagged. If either stream 00074 // runs out of data, it will synthesize blank video 00075 // frames and silent audio samples as necessary to 00076 // satisfy read requests. 00077 // 00078 // Some AVI files have incorrect length values encoded 00079 // into them - usually, they're a second or two long or 00080 // short. When playing such an AVI using the Movie class, 00081 // you may see a slightly truncated video, or a slightly 00082 // elongated video (padded with black frames). There are 00083 // utilities out there to fix the length values in AVI 00084 // files. 00085 // 00086 //////////////////////////////////////////////////////////////////// 00087 INLINE double MovieVideoCursor:: 00088 length() const { 00089 return _length; 00090 } 00091 00092 //////////////////////////////////////////////////////////////////// 00093 // Function: MovieVideoCursor::can_seek 00094 // Access: Published 00095 // Description: Returns true if the movie can seek. If this is 00096 // true, seeking is still not guaranteed to be fast: 00097 // for some movies, seeking is implemented by rewinding 00098 // to the beginning and then fast-forwarding to the 00099 // desired location. Even if the movie cannot seek, 00100 // the fetch methods can still advance to an arbitrary 00101 // location by reading frames and discarding them. 00102 // However, to move backward, can_seek must return true. 00103 //////////////////////////////////////////////////////////////////// 00104 INLINE bool MovieVideoCursor:: 00105 can_seek() const { 00106 return _can_seek; 00107 } 00108 00109 //////////////////////////////////////////////////////////////////// 00110 // Function: MovieVideoCursor::can_seek_fast 00111 // Access: Published 00112 // Description: Returns true if seek operations are constant time. 00113 //////////////////////////////////////////////////////////////////// 00114 INLINE bool MovieVideoCursor:: 00115 can_seek_fast() const { 00116 return _can_seek_fast; 00117 } 00118 00119 //////////////////////////////////////////////////////////////////// 00120 // Function: MovieVideoCursor::aborted 00121 // Access: Published 00122 // Description: Returns true if the video has aborted prematurely. 00123 // For example, this could occur if the Movie was actually 00124 // an internet TV station, and the connection was lost. 00125 // Reaching the normal end of the video does not 00126 // constitute an 'abort' condition. 00127 //////////////////////////////////////////////////////////////////// 00128 INLINE bool MovieVideoCursor:: 00129 aborted() const { 00130 return _aborted; 00131 } 00132 00133 //////////////////////////////////////////////////////////////////// 00134 // Function: MovieVideoCursor::streaming 00135 // Access: Published 00136 // Description: Returns true if the video frames are being "pushed" 00137 // at us by something that operates at its own speed - 00138 // for example, a webcam. In this case, the frames come 00139 // when they're ready to come. Attempting to read too 00140 // soon will produce nothing, reading too late will cause 00141 // frames to be dropped. In this case, the ready flag 00142 // can be used to determine whether or not a frame is 00143 // ready for reading. 00144 // 00145 // When streaming, you should still pay attention to 00146 // last_start, but the value of next_start is only a 00147 // guess. 00148 //////////////////////////////////////////////////////////////////// 00149 INLINE bool MovieVideoCursor:: 00150 streaming() const { 00151 return _streaming; 00152 } 00153 00154 //////////////////////////////////////////////////////////////////// 00155 // Function: MovieVideoCursor::ready 00156 // Access: Published 00157 // Description: Returns true if the cursor is a streaming source, and 00158 // if a video frame is ready to be read. For non- 00159 // streaming sources, this is always false. 00160 //////////////////////////////////////////////////////////////////// 00161 INLINE bool MovieVideoCursor:: 00162 ready() const { 00163 return _ready; 00164 } 00165