随心所欲控制VR全景各场景声音

我们之前曾经谈过如何在保持全局背景音乐的同时，还能在切换场景时，让每个场景的声音（解说词）都不一样。也就是如果有十个场景，那每个场景都有自己的解说词，当从场景A到场景B时，场景A的声音就会停止，然后播放场景B的声音，我们提供了以下的解决方案：

<krpano onstart="playsound(bg, backgroundmusic.mp3,0); loadscene(scene1,null,MERGE);">
<plugin name="soundinterface" url="soundinterface.swf" alturl="soundinterface.js" preload="true" />
<scene name="scene1">
<events name="scene1events" onxmlcomplete="tween(sound[bg].volume, 0.5);playsound(scene1sound, scene1music.mp3,1,tween(sound[bg].volume, 1));" onremovepano="stopsound(scene1sound);" />
...
scene>
<scene name="scene2">
<events name="scene2events" onxmlcomplete="tween(sound[bg].volume, 0.5);playsound(scene2sound, scene2music.mp3,1,tween(sound[bg].volume, 1));" onremovepano="stopsound(scene2sound);" />
...
scene>
krpano>

现在，我们来讲讲如何随心所欲的来控制场景的音乐，我们来假设这么一种情况。有三个展厅，每个展厅我们有三个场景，但我们只有三个解说词对应着这三个展厅，也就是当同一展厅的场景互相切换时，我们需要解说词是持续的，而不是因场景的变换而停止或重新开始。例如展厅1的场景a、b、c之间的相互切换，或者展厅2的场景d、e、f的相互切换时，其解说词是流动的，只有当不同展厅的场景切换时，才会中止之前展厅的解说词，而开始新的展厅的解说词，例如从展厅1的场景b到展厅2的场景f。

我们来假定四个场景，其中第一个场景和第三个场景属于一个“展厅”，第二个和第四个场景属于另外一个“展厅”，至于全局音乐为了方便，我们暂时不添加。

<krpano>
<plugin name="soundinterface" url="soundinterface.swf" alturl="soundinterface.js" preload="true" />
<skin_settings ...
...
musicgroup="0" />
<scene name="scene1"… group="1">
<events name="scene1events"
onxmlcomplete="ifnot(scene[get(xml.scene)].group == skin_settings.musicgroup,
playsound(scene1sound, scene1music.mp3,1);
copy(skin_settings.musicgroup,scene[get(xml.scene)].group));"
onremovepano="ifnot(scene[get(xml.scene)].group == skin_settings.musicgroup,stopsound(scene1sound));" />
...
scene>
<scene name="scene2"… group="2">
<events name="scene2events"
onxmlcomplete="ifnot(scene[get(xml.scene)].group == skin_settings.musicgroup,
playsound(scene2sound, scene2music.mp3,1);
copy(skin_settings.musicgroup,scene[get(xml.scene)].group));"
onremovepano="ifnot(scene[get(xml.scene)].group == skin_settings.musicgroup,stopsound(scene2sound));" />
...
scene>
<scene name="scene3"… group="1">
<events name="scene3events"
onxmlcomplete="ifnot(scene[get(xml.scene)].group == skin_settings.musicgroup,
playsound(scene1sound, scene1music.mp3,1);
copy(skin_settings.musicgroup,scene[get(xml.scene)].group));"
onremovepano="ifnot(scene[get(xml.scene)].group == skin_settings.musicgroup,stopsound(scene1sound));" />
...
scene>
<scene name="scene4"… group="2">
<events name="scene4events"
onxmlcomplete="ifnot(scene[get(xml.scene)].group == skin_settings.musicgroup,
playsound(scene2sound, scene2music.mp3,1);
copy(skin_settings.musicgroup,scene[get(xml.scene)].group));"
onremovepano="ifnot(scene[get(xml.scene)].group == skin_settings.musicgroup,stopsound(scene2sound));" />
...
scene>
krpano>