DirectFB 之 通过多Window实现多元素处理

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设计

    采用多window的方式实现显示，因为每个window可以独立的属性，比如刷新频率，也是我们最关注的

示例

/**********************************************
 * Author: younger.liucn@hotmail.com
 * File name: dfbFont.c
 * Description:  dfbFont
 * Version, Desc
 *  1.1    Created
 *  1.2    add config
 **********************************************/

#include <stdio.h>
#include <stdlib.h>
#include <unistd.h>
#include <fcntl.h>
#include <errno.h>
#include <string.h>

#include <time.h>
#include <sys/time.h>
#include <directfb.h>

#include "dfbFont.h"

/* config information */
#define DFB_LAYERID_USING        0
#define DFB_FONT_TYPE_1 "/home/younger/DFB/Font/data/decker.ttf"


/*********************************************************
 * log flags and func of debug and error infor.[Begin]
 ********************************************************/


#ifdef _DFB_DEBUG_
#define DFB_DEBUG(format, ...)    do {       
    printf("[BootAnimation:%4dL]DEBUG: "format, __LINE__, ##__VA_ARGS__);  
} while (0)
#else
#define DFB_DEBUG(format, ...)    do {} while (0)
#endif

#define DFB_NOTICE(format, ...)    do {       
    printf("[BootAnimation:%4dL]INFO: "format, __LINE__, ##__VA_ARGS__);  
} while (0)

#define DFB_ERROR(format, ...)    do {       
    printf("[BootAnimation:%4dL]ERROR: "format, __LINE__, ##__VA_ARGS__);  
} while (0)
/*********************************************************
 * log flags and func of debug and error infor.[End]
 ********************************************************/

/*********************************************************
 * Data structure and Global variants [Begin]
 ********************************************************/
/* 使用directFB画图所需的DFB资源 */
struct DfbResDsc {
    IDirectFB               *dfb;
    IDirectFBDisplayLayer	*layer;
};
static struct DfbResDsc badsc;

struct WinResDsc {
    IDirectFBWindow			*window;
    IDirectFBSurface		*surface;
};
static struct WinResDsc winText;
/* 如果位置值(OFFSET_X或OFFSET_Y)设置为-1,表示居中显示 */
#define WINDOW_TEXT_LEN_X	(800)
#define WINDOW_TEXT_LEN_Y	(100)
#define WINDOW_TEXT_OFFSET_X	(-1)
#define WINDOW_TEXT_OFFSET_Y	(500)
static char *testString = "Hello world! This is DirectFB!";

static struct WinResDsc winAnim;
/* 如果位置值(OFFSET_X或OFFSET_Y)设置为-1,表示居中显示 */
#define WINDOW_ANIM_LEN_X	(200)
#define WINDOW_ANIM_LEN_Y	(200)
#define WINDOW_ANIM_OFFSET_X	(-1)
#define WINDOW_ANIM_OFFSET_Y	(200)

/* config information */
#define ANIM_IMAGES_COUNT         48
/* support png, jpg */
#define ANIM_IMAGE_FORMAT         "png"
#define ANIM_FILE_NAME_MAX_SIZE   255
#define ANIM_IMG_DEFAULT_WIDTH    186
#define ANIM_IMG_DEFAULT_HEIGHT   186
#define ANIM_IMG_DEFAULT_FPS      10
#define ANIM_MAX_RUNNING_MTIME            (20000)

#define ANIM_DEFAULT_LOGO_PATH    "/home/liuyiy/DFB/FontAnim/data/images"

static IDirectFBSurface *imgSfc[ANIM_IMAGES_COUNT];
/*********************************************************
 * Data structure and Global variants [End]
 ********************************************************/
 
/* 初始化/释放资源dfb/layer  [Begin] */
void freeResources()
{
    /* Release the layer. */
    if (badsc.layer)
        badsc.layer->Release(badsc.layer);

    badsc.dfb->Release(badsc.dfb);

    return ;
}

static void initResources(int argc, char **argv)
{
    DFBResult ret;
    badsc.dfb	    = NULL;
    IDirectFB *dfb  = NULL;

	/* 初始化DirectFB */
    DirectFBInit(&argc, &argv);
    DirectFBCreate(&dfb);
    if (!dfb) {
        DFB_ERROR("directfb interface is NULL
");
        return ;
    }
    badsc.dfb = dfb;

    /* 初始化 display layer：其中DFB_LAYERID_USING设置为0.*/
    ret = badsc.dfb->GetDisplayLayer(badsc.dfb, DFB_LAYERID_USING, &(badsc.layer));
    if(ret != (DFBResult)DFB_OK) {
        DFB_ERROR("Get layer(%d) failed!
", DFB_LAYERID_USING);
        goto fail;
    } else {
        DFB_DEBUG("Get layer(%d) independently.
", DFB_LAYERID_USING);
    }

    return ;
fail:
    freeResources();
    return ;
}
/* 初始化/释放资源dfb/layer  [End] */

/* 初始化/释放资源WinResDsc  [Begin] */
static void deinitWinRes(struct WinResDsc *winres)
{

    winres->surface->SetColor(winres->surface, 0, 0, 0, 0);
    winres->surface->Clear(winres->surface, 0, 0, 0, 0);
    winres->surface->Flip(winres->surface, NULL, DSFLIP_WAITFORSYNC);
	
    /* Release the window's surface. */
    if(winres->surface)
        winres->surface->Release(winres->surface);
    /* Release the window. */
    if (winres->window)
        winres->window->Release(winres->window);

    return ;
}

static void initWinResPercent(struct WinResDsc *winres,
						int window_offset_x,
						int window_offset_y,
						int window_len_x,
						int window_len_y
						)
{
    DFBResult ret;
    IDirectFBWindow			*window		= NULL;
    IDirectFBSurface		*surface	= NULL;
    DFBWindowDescription	desc;
    DFBDisplayLayerConfig	config;

    /* 获取display layer的配置，. */
    badsc.layer->GetConfiguration(badsc.layer, &config);

    /* 设置window参数，并创建Window */
    desc.flags   = (DFBWindowDescriptionFlags)(DWDESC_POSX | DWDESC_POSY | DWDESC_WIDTH | DWDESC_HEIGHT | DWDESC_CAPS | DWDESC_OPTIONS);
    DFB_NOTICE("Layer Screen width %d, height %d !
", config.width, config.height);
	/* 固定window在layer的中位置 */
	if (-1 == window_offset_x) {
		desc.posx    = (config.width - window_len_x) / 2;
	} else {
		desc.posx    = window_offset_x;
	}
	if (-1 == window_offset_y) {
		desc.posy    = (config.height - window_len_y) / 2;
	} else {
		desc.posy    = window_offset_y;
	}
    desc.width   = window_len_x;
    desc.height  = window_len_y;
    desc.caps    = (DFBWindowCapabilities)(DWCAPS_NODECORATION);
    desc.options = (DFBWindowOptions) (DWOP_GHOST);
    ret = badsc.layer->CreateWindow(badsc.layer, &desc, &window);
    if(ret != (DFBResult)DFB_OK) {
        DFB_ERROR("Create window failed!
");
		return ;
    }

	/* 设置透明度 */
    ret = window->SetOpacity(window, 0xFF);
    if(ret != (DFBResult)DFB_OK) {
        DFB_ERROR("SetOpacity failed!
");
        window->Release(window);
		return ;
    }

    /* 获取window的surface. */
    ret = window->GetSurface(window, &surface);
    if(ret != (DFBResult)DFB_OK) {
        DFB_ERROR("GetSurface failed!
");
		return ;
    }
	/*若不执行clear，则可能出现花屏*/
    surface->SetColor(surface, 0, 0, 0, 0);
    surface->Clear(surface, 0, 0, 0, 0);
    surface->Flip(surface, NULL, DSFLIP_WAITFORSYNC);
	winres->window = window;
	winres->surface = surface;
    return ;
}
/* 初始化/释放资源WinResDsc  [End] */

/* 绘制字符串 */
static void flipText(char* str) {
    int width = 0, height = 0;
	IDirectFBFont* font = NULL;
    DFBFontDescription font_desc;
    IDirectFBSurface *surface = winText.surface;

    surface->GetSize(surface, &width, &height);

	/* font init */
    font_desc.flags = DFDESC_HEIGHT;
    font_desc.height = height / 2;
	badsc.dfb->CreateFont(badsc.dfb, DFB_FONT_TYPE_1, &font_desc, &font);

    surface->Clear(surface, 0x0, 0x0, 0x0, 0xff);
    surface->SetFont(surface, font);
	/* 设置前景颜色 */
    surface->SetColor(surface, 0x00, 0xFF, 0x00, 0xFF);
    surface->DrawString(surface, str, strlen(str), width / 2, height / 2, DSTF_CENTER);
    /* 变换、更新surface buffer */
	surface->Flip(surface, NULL, DSFLIP_WAITFORSYNC);
	return ;
}


/* 绘制动画 [Begin] */
static inline int checkFileExist(const char *filename)
{
    if((access(filename, R_OK)) != -1)
        return 1;

    return 0;
}
static int doLoadImg(const char  *filename,
                        IDirectFBSurface      **surface,
                        unsigned int           *width,
                        unsigned int           *height)
{
    int ret;
    IDirectFB *dfb = badsc.dfb;
    DFBSurfaceDescription img_dsc;
    IDirectFBImageProvider *provider = NULL;

    if(NULL == surface || NULL == filename) {
        DFB_ERROR("doLoadImg() failed for %d.
", -EINVAL);
        return -EINVAL;
    }

    DFB_DEBUG("doLoadImg() entry:%s .
", filename);
	/* 检查图片是否存在 */
    if(!checkFileExist(filename)) {
        DFB_ERROR("file %s does not exist.
", filename);
        return -EINVAL;
    }

    /* 将要显示的图片及其相关信息保存在一个image provider中 */
    ret = dfb->CreateImageProvider(dfb, filename, &provider);
    if(ret) {
        DFB_ERROR("CreateImageProvider() for %s failed %d.
", filename, ret);
        return ret;
    }

    /* 将保存在provider中的图片信息提取出来，存于surface description中 */
    ret = provider->GetSurfaceDescription(provider, &img_dsc);
    if(ret) {
        DFB_ERROR("GetSurfaceDescription() for %s failed %d.
",
                filename, ret);
        provider->Release(provider);
        return ret;
    }

    /* 根据surface description创建surface，尺寸与图片大小完全一致 */
    ret = dfb->CreateSurface(dfb, &img_dsc, surface);
    if(ret) {
        DFB_ERROR("CreateSurface() for %s failed %d.
", filename, ret);
        provider->Release(provider);
        return ret;
    }

    /* 将图片呈递给刚才建立的logo平面，如果大小不一致，则进行缩放 */
    ret = provider->RenderTo(provider, *surface, NULL);
    if(ret) {
        DFB_ERROR("RenderTo() for %s failed %d.
", filename, ret);
        (*surface)->Release(*surface);
        provider->Release(provider);
        return ret;
    }

    /* Return width / height? */
    if(width) {
        *width = img_dsc.width;
    }
    if(height){
        *height  = img_dsc.height;
    }

    /* release provider */
    provider->Release(provider);

    DFB_DEBUG("doLoadImg() exit.
");
    return ret;
}

/* 释放图片资源 */
static void deinitImages()
{
  int i = 0;
  for (i = 0; i < ANIM_IMAGES_COUNT; i++) {
      if (imgSfc[i]) {
          imgSfc[i]->Release(imgSfc[i]);
      } else {
          break;
      }
  }
  return ;
}
/* 初始化图片资源 */
static int initImages()
{
    int ret = 0, i = 0;
    char filename[ANIM_FILE_NAME_MAX_SIZE];
    IDirectFBSurface *tmp_sfc = NULL;

    for (i = 0; i < ANIM_IMAGES_COUNT; i++) {
        imgSfc[i] = NULL;
    }

    for (i = 0; i < ANIM_IMAGES_COUNT; i++) {
        tmp_sfc = NULL;
        memset(filename, 0x0, sizeof(filename));
        snprintf(filename, ANIM_FILE_NAME_MAX_SIZE,
				"%s/%02d.%s", ANIM_DEFAULT_LOGO_PATH, i, ANIM_IMAGE_FORMAT);
        ret = doLoadImg(filename, &tmp_sfc, NULL, NULL);
        if (ret != 0) {
            goto bail;
        }
        imgSfc[i] = tmp_sfc;
    }

    return 0;
bail:
    deinitImages();
    return -1;
}


static void fillDFBSurface(
                        IDirectFBSurface *primary_sfc,
                        IDirectFBSurface *img_sfc,
                        int x, int y)
{
    primary_sfc->Clear(primary_sfc, 0, 0, 0, 255);
	/* 
     * blit即将两张位图（即thiz和source）按拉操作的方法组合成一张图片。 
     * 在DirectFB中，其定义的动作也是合理的：将img_sfc blit到primary_sfc上去， 
     * 两个平面上的内容会产生叠加 
     */ 
    primary_sfc->Blit(primary_sfc, img_sfc, NULL, x, y);
	/* 变换、更新surface buffer */  
    primary_sfc->Flip(primary_sfc, NULL, DSFLIP_WAITFORSYNC);

    return ;
}

/* 获取b与a的时间差，单位：毫秒 */
static unsigned long deltaMsecs(struct timespec *a,
        struct timespec *b)
{
    long delta_secs = 0, delta_msecs = 0;

    if(a->tv_sec < b->tv_sec ||
            (a->tv_sec == b->tv_sec && a->tv_nsec < b->tv_nsec)) {
        return 0;
    }

    delta_secs = a->tv_sec - b->tv_sec;
    delta_msecs = (a->tv_nsec - b->tv_nsec) / 1000000;
    while(delta_msecs < 0) {
        delta_secs--;
        delta_msecs += 1000;
    }

    return delta_secs * 1000 + delta_msecs;
}

static void doAnimation()
{
    int ret, i;
    struct timespec before_draw, after_draw;
    unsigned long elapsed_msec, total_msec;
    IDirectFBSurface *primary = winAnim.surface;
    unsigned long interval = (1000 / ANIM_IMG_DEFAULT_FPS);
	
    if (initImages()) {
        DFB_ERROR("Init images failed!
");
        return ;
    }

    DFB_NOTICE("Animation start ...
");
    total_msec = 0;
    i  = 0;
    do {
        if(i >= ANIM_IMAGES_COUNT) {
            i = 0;
        }

        clock_gettime(CLOCK_MONOTONIC, &before_draw);
        fillDFBSurface(primary, imgSfc[i],
                0,0);
        clock_gettime(CLOCK_MONOTONIC, &after_draw);
		/*
		 * 获取画图前后两次的时间差elapsed_msec
		 * 如果elapsed_msec>interval,则不再休眠
		 * 否则休眠interval-elapsed_msec
		 */
        elapsed_msec = deltaMsecs(&after_draw, &before_draw);
        if(elapsed_msec < interval) {
            usleep((interval - elapsed_msec) * 1000);
            total_msec += interval;
        } else {
            total_msec += elapsed_msec;
        }
        DFB_DEBUG("elapsed %lu ms 
",
                        elapsed_msec < interval ? interval : elapsed_msec);
        if(total_msec >= ANIM_MAX_RUNNING_MTIME) {
            DFB_NOTICE("Stopped by Timeout(%lu).
", total_msec);
            break;
        }

        i++;
    } while(1);

out:
    DFB_NOTICE("Animation exit with black screen...
");
    deinitImages();

    return ;
}
/* 绘制动画 [End] */

static void doShow()
{
    DFB_NOTICE("Text start ...
");
	flipText(testString);
	doAnimation();

    return ;
}

int main(int argc, char **argv)
{
    DFB_NOTICE("Animation entry.
");
    initResources(argc, argv);
	initWinResPercent(&winText,
			WINDOW_TEXT_OFFSET_X, WINDOW_TEXT_OFFSET_Y,
			WINDOW_TEXT_LEN_X, WINDOW_TEXT_LEN_Y);
	initWinResPercent(&winAnim,
			WINDOW_ANIM_OFFSET_X, WINDOW_ANIM_OFFSET_Y,
			WINDOW_ANIM_LEN_X, WINDOW_ANIM_LEN_Y);
    doShow();
	deinitWinRes(&winText);
	deinitWinRes(&winAnim);
    freeResources();

    DFB_NOTICE("Animation exit.
");
    return 0;
}