DirectFB 之 实例图像不断右移

/**********************************************
 * Author: younger.liucn@gmail.com
 * File name: imgrotate.c
 * Description: animation
 * Modified:
 *   date:   2014-01-06  create
 *********************************************/
#include <directfb.h>

#include "animation.h"

#define MAX_LOOP        2
#define INTERVAL_PIXEL   2
#define EYE_HZ          50
#define INTERVAL_TIME   (1000 / EYE_HZ)

static int animation(int argc, char **argv);

int main(int argc, char **argv)
{
    return  animation(argc, argv);
}

static int animation(int argc, char **argv)
{
    int i, loop = 0;
    int screen_width = 0, screen_height = 0;
    DFBSurfaceDescription dsc;
    /*
     * For collecting infomation of image,
     * and provide image to IDirectFBSurface
     */
    IDirectFBImageProvider *provider;
    IDirectFB *dfb = NULL;
    IDirectFBSurface *primary = NULL;
    IDirectFBSurface *logo = NULL;

    /* 初始化整个DirectFB库，为后续画图等操作做准备 */
    DirectFBInit(&argc, &argv);
    DirectFBCreate(&dfb);
    
    /* 设置协作等级为全屏模式,具体请阅读SetCooperativeLevel接口解析 */
    dfb->SetCooperativeLevel(dfb, DFSCL_FULLSCREEN);
    dsc.flags = DSDESC_CAPS;
    dsc.caps = DSCAPS_PRIMARY | DSCAPS_FLIPPING;

    /* 根据dsc创建一个基本平面 */
    dfb->CreateSurface(dfb, &dsc, &primary);
    /* 获取该基本平面的宽度和高度 */
    primary->GetSize(primary, &screen_width, &screen_height);

    /* 将要显示的图片及其相关信息保存在provider中 */
    dfb->CreateImageProvider(dfb, BA_IMG_NAME, &provider);

    /* 将保存在provider中的图片信息提取出来，存于dsc中 */
    provider->GetSurfaceDescription(provider, &dsc);

    /* 根据dsc创建一个图像平面 */
    dfb->CreateSurface(dfb, &dsc, &logo);

    /* 将图片呈递给刚才建立的logo平面，如果大小不一，则进行缩放 */
    provider->RenderTo(provider, logo, NULL);

    /* 释放资源provider */
    provider->Release(provider);

    for (i = -dsc.width;
            i < screen_width && !ba_check_exit(shared_mem);
            i = i + INTERVAL_PIXEL) {
        /* 清空屏幕 */
        primary->FillRectangle(primary, 0, 0,
                    screen_width, screen_height);
        primary->Blit(primary, logo, NULL, i,
                    (screen_height - dsc.height) / 2);
        /*
         * Blit model:将图片blit到平面
         * Blit(IDirectFBSurface *thiz, IDirectFBSurface *source,
         *          const DFBRectangle *source_rect, int x, int y);
         * if source_rect == NULL，use entire surface.
         * DFBRctangle is rectangular frame defined by two points.
         * (x, y):the point of top left corner.
         */

        /* flit整个屏幕 */
        primary->Flip(primary, NULL, DSFLIP_WAITFORSYNC);

        msleep(INTERVAL_TIME);

        if ((screen_width - INTERVAL_PIXEL) <= i && loop < MAX_LOOP) {
            BA_LOG(1, "screen_%d, loop:%d.
", screen_width, loop);
            loop++;
            i = -dsc.width;
        }

    }

    logo->Release(logo);
    primary->Release(primary);
    dfb->Release(dfb);
    return 0;
}