使用PainterEngine开发音乐播放器

这是一个支持WAV格式的音乐带有频谱与进度控制的简易音乐播放器,可以在windows android iOS上无缝移植.目前仅支持wav 44100HZ 16bits格式的音乐播放,不过对于格式支持的拓展,应该不是什么难事。

目前代码和示范程序都可以在PainterEngine.com中下载到

编译运行

1.为了编译源码,作为示范你需要先安装mingw(当然其它平台和其它编译器也可,你可以参照PainterEngine.com中的教程部分),运行cmd,输入gcc –v,验证你的mingw是否安装成功

2.访问PainterEngine.com,下载PainterEngine

3.访问PainterEngine.com的实例,下载音乐播放器的源码

4.将解压出来的project中的代码文件,替换PainterEngine/project,并将bin中的gbk_18.pxf放在PainterEngine/project文件夹中

5.进入PainterEngine/platform/windows,运行mingw_build.bat,等待编译完成即可

代码解析

#ifndef PAINTERENGINE_APPLICATION_H

#define PAINTERENGINE_APPLICATION_H

#include "PainterEngine_Startup.h"

#include "platform/modules/px_audio.h"

typedef struct

{

PX_Runtime runtime;

//根对象,选择音乐按钮,暂停按钮,文件选择器,进度条

PX_Object *root,*button_play,*button_pause,*explorer_file,*sliderbar_progress;

//音频数据

PX_SoundData sounddata;

//混音器

PX_SoundPlay soundplay;

//字模

PX_FontModule fm;

}PX_Application;

extern PX_Application App;

px_bool PX_ApplicationInitialize(PX_Application *App,px_int screen_Width,px_int screen_Height);

px_void PX_ApplicationUpdate(PX_Application *App,px_dword elpased);

px_void PX_ApplicationRender(PX_Application *App,px_dword elpased);

px_void PX_ApplicationPostEvent(PX_Application *App,PX_Object_Event e);

#endif

#include "PainterEngine_Application.h"

//////////////////////////////////////////////////////////////////////////

//更多代码实例/教程访问www.PainterEngine.com

//////////////////////////////////////////////////////////////////////////

PX_Application App;

//返回path目录中文件夹个数

px_int APP_ExplorerGetPathFolderCount(const px_char *path,const char *filter)

{

return PX_FileGetDirectoryFileCount(path,PX_FILEENUM_TYPE_FOLDER,filter);

}

//返回path目录中文件个数

px_int APP_ExplorerGetPathFileCount(const px_char *path,const char *filter)

{

return PX_FileGetDirectoryFileCount(path,PX_FILEENUM_TYPE_FILE,"wav\0WAV\0Wav\0");

}

//取得path目录中文件夹名称

px_int APP_ExplorerGetPathFolderName(const char path[],int count,char FileName[][260],const char *filter)

{

return PX_FileGetDirectoryFileName(path,count,FileName,PX_FILEENUM_TYPE_FOLDER,filter);

}

//取得path目录中文件名称,当然加上过滤器仅接受wav文件

px_int APP_ExplorerGetPathFileName(const char path[],int count,char FileName[][260],const char *filter)

{

return PX_FileGetDirectoryFileName(path,count,FileName,PX_FILEENUM_TYPE_FILE,"wav\0WAV\0Wav\0");

}

//当explorer

px_void PX_ApplicationOnExpolrerConfirm(PX_Object *pObject,PX_Object_Event e,px_void *ptr)

{

PX_Application *pApp=(PX_Application *)ptr;

px_char sPath[260];

//取得选择的目录

PX_Object_ExplorerGetPath(pObject,sPath,0);

if (sPath[0])

{

//清理之前的播放音乐

PX_SoundPlayClear(&pApp->soundplay);

//释放之前的音乐数据

PX_SoundStaticDataFree(&pApp->sounddata);

//加载音乐播放数据

if(!PX_LoadSoundFromFile(&pApp->runtime.mp_resources,&pApp->sounddata,sPath))return;

//将播放数据导入混音器

PX_SoundPlayAdd(&pApp->soundplay,PX_SoundCreate(&pApp->sounddata,PX_FALSE));

//设置进度条范围

PX_Object_SliderBarSetRange(pApp->sliderbar_progress,0,pApp->sounddata.size);

}

//当选择音乐按钮被点击后

px_void PX_ApplicationOnButtonPlay(PX_Object *pObject,PX_Object_Event e,px_void *ptr)

{

PX_Application *pApp=(PX_Application *)ptr;

//打开文件选择菜单

PX_Object_ExplorerOpen(pApp->explorer_file);

}

//当暂停播放音乐被点击后

px_void PX_ApplicationOnButtonPause(PX_Object *pObject,PX_Object_Event e,px_void *ptr)

{

PX_Application *pApp=(PX_Application *)ptr;

if (PX_SoundPlayGetDataCount(&pApp->soundplay)==0)

{

//没有音乐播放,直接返回

return;

}

if (pApp->soundplay.pause)

{

//如果当前暂停播放,将按钮文本设置为暂停

PX_Object_PushButtonSetText(pObject,"暂停");

//继续播放音乐

PX_SoundPlayPause(&pApp->soundplay,PX_FALSE);

}

else

{

//如果当前正在播放,将按钮文本设置为继续

PX_Object_PushButtonSetText(pObject,"继续");

//暂停播放音乐

PX_SoundPlayPause(&pApp->soundplay,PX_TRUE);

}

px_void PX_ApplicationOnProgressChanged(PX_Object *pObject,PX_Object_Event e,px_void *ptr)

{

PX_Application *pApp=(PX_Application *)ptr;

px_int offset;

//将按钮文本设置为继续

PX_Object_PushButtonSetText(pApp->button_pause,"继续");

//暂停播放

PX_SoundPlayPause(&pApp->soundplay,PX_TRUE);

//播放数据偏移应该至少4字节对齐(2声道,16位),我这里直接8字节对齐

offset=PX_Object_SliderBarGetValue(pObject);

offset=offset/8*8;

//重新设置播放偏移量

pApp->soundplay.Sounds[0].offset=offset;

}

px_bool PX_ApplicationInitialize(PX_Application *pApp,px_int screen_width,px_int screen_height)

{

px_int x=5,y=5;

PX_ApplicationInitializeDefault(&pApp->runtime, screen_width, screen_height);

//初始化混音器

PX_SoundPlayInitialize(&pApp->runtime.mp_game,&pApp->soundplay);

//*初始化播放器

PX_AudioInitialize(&pApp->soundplay);

//初始化字模库

if(!PX_FontModuleInitialize(&pApp->runtime.mp_resources,&pApp->fm))return PX_FALSE;

//加载字模库

if(!PX_LoadFontModuleFromFile(&pApp->fm,"gbk_18.pxf"))return PX_FALSE;

//创建根对象

pApp->root=PX_ObjectCreate(&pApp->runtime.mp_ui,PX_NULL,0,0,0,0,0,0);

//创建文件浏览器

pApp->explorer_file=PX_Object_ExplorerCreate(&pApp->runtime.mp_ui,pApp->root,0,0,pApp->runtime.surface_width,pApp->runtime.surface_height,&pApp->fm,

APP_ExplorerGetPathFolderCount,

APP_ExplorerGetPathFileCount,

APP_ExplorerGetPathFolderName,

APP_ExplorerGetPathFileName,

);

//绑定确定事件

PX_ObjectRegisterEvent(pApp->explorer_file,PX_OBJECT_EVENT_EXECUTE,PX_ApplicationOnExpolrerConfirm,pApp);

//创建播放按钮

pApp->button_play=PX_Object_PushButtonCreate(&pApp->runtime.mp_ui,pApp->root,x,y,128,24,"选择音乐",&pApp->fm);

//绑定播放函数

PX_ObjectRegisterEvent(pApp->button_play,PX_OBJECT_EVENT_EXECUTE,PX_ApplicationOnButtonPlay,pApp);

x+=136;

//创建暂停按钮

pApp->button_pause=PX_Object_PushButtonCreate(&pApp->runtime.mp_ui,pApp->root,x,y,128,24,"暂停",&pApp->fm);

//绑定播放函数

PX_ObjectRegisterEvent(pApp->button_pause,PX_OBJECT_EVENT_EXECUTE,PX_ApplicationOnButtonPause,pApp);

//创建播放进度条

y+=32;

x=10;

pApp->sliderbar_progress=PX_Object_SliderBarCreate(&pApp->runtime.mp_ui,pApp->root,x,y,pApp->runtime.surface_width-20,32,PX_OBJECT_SLIDERBAR_TYPE_HORIZONTAL,PX_OBJECT_SLIDERBAR_STYLE_BOX);

PX_Object_SliderBarSetSliderButtonLength(pApp->sliderbar_progress,32);

PX_Object_SliderBarSetRange(pApp->sliderbar_progress,0,100);

//绑定进度条事件

PX_ObjectRegisterEvent(pApp->sliderbar_progress,PX_OBJECT_EVENT_VALUECHANGED,PX_ApplicationOnProgressChanged,pApp);

return PX_TRUE;

}

px_void PX_ApplicationUpdate(PX_Application *pApp,px_dword elpased)

{

}

#define FRAME_SIZE 1024

px_void PX_ApplicationRender(PX_Application *pApp,px_dword elpased)

{

px_int lheight;

px_complex frame[FRAME_SIZE];

px_double hanning[FRAME_SIZE];

px_int16 uframe[FRAME_SIZE];

px_surface *pRenderSurface=&pApp->runtime.RenderSurface;

//清理画布

PX_RuntimeRenderClear(&pApp->runtime,PX_OBJECT_UI_DEFAULT_BACKGROUNDCOLOR);

//开始绘制频谱

pApp->sliderbar_progress->Width=pRenderSurface->width-20.f;

//抓取1024长度的音频帧做分析

if(PX_SoundPlayReadCurrentPlayingData(&pApp->soundplay,0,0,uframe,1024))

{

px_int i;

PX_Object_SliderBarSetValue(pApp->sliderbar_progress,pApp->soundplay.Sounds[0].offset);

//构建汉宁窗

PX_WindowFunction_hanning(hanning,FRAME_SIZE);

for(i=0;i<FRAME_SIZE;i++)

{

//归一化,加窗

frame[i].re=uframe[i]*1.0/32768.0*hanning[i];

frame[i].im=0;

}

//快速傅里叶变换

PX_FFT(frame,frame,FRAME_SIZE);

//计算功率谱,然后缩放一下

for(i=0;i<FRAME_SIZE/2;i++)

{

frame[i].re=PX_sqrtd(frame[i].re*frame[i].re+frame[i].im*frame[i].im)/50;

}

//依据傅里叶变换共轭对称性,只需要处理一半频谱

for (i=0;i<FRAME_SIZE/2;i++)

{

px_int j;

//计算最终高度

lheight=(px_int)(frame[i].re>1?pRenderSurface->height:pRenderSurface->height*frame[i].re);

lheight=(px_int)(lheight*0.85);

//绘制频谱像素

for(j=0;j<lheight;j++)

{

px_uchar r=(px_uchar)(j*255/lheight);

r=(r>255?255:r);

PX_SurfaceDrawPixel(pRenderSurface,pRenderSurface->width/2+i,pRenderSurface->height-1-j,PX_COLOR(255-r,r,255-r,255-r));

PX_SurfaceDrawPixel(pRenderSurface,pRenderSurface->width/2-i,pRenderSurface->height-1-j,PX_COLOR(255-r,r,255-r,255-r));

}

//渲染控件

PX_ObjectRender(pRenderSurface,pApp->root,elpased);

}

px_void PX_ApplicationPostEvent(PX_Application *pApp,PX_Object_Event e)

{

PX_ApplicationEventDefault(&pApp->runtime, e);

//处理按键消息

PX_ObjectPostEvent(pApp->root,e);

}