fbdev: change API to make easier to avoid glitches

git-svn-id: file:///home/notaz/opt/svn/PicoDrive@912 be3aeb3a-fb24-0410-a615-afba39da0efa

diff --git a/platform/linux/fbdev.c b/platform/linux/fbdev.c
index b4889ea..bcef0fc 100644 (file)
--- a/platform/linux/fbdev.c
+++ b/platform/linux/fbdev.c
@@ -61,7 +61,8 @@ void vout_fbdev_wait_vsync(struct vout_fbdev *fbdev)
        ioctl(fbdev->fd, FBIO_WAITFORVSYNC, &arg);
 }
 
-int vout_fbdev_resize(struct vout_fbdev *fbdev, int w, int h, int bpp,
+/* it is recommended to call vout_fbdev_clear() before this */
+void *vout_fbdev_resize(struct vout_fbdev *fbdev, int w, int h, int bpp,
                      int left_border, int right_border, int top_border, int bottom_border, int buffer_cnt)
 {
        int w_total = left_border + w + right_border;
@@ -83,13 +84,20 @@ int vout_fbdev_resize(struct vout_fbdev *fbdev, int w, int h, int bpp,
                fbdev->fbvar_new.xres_virtual = w_total;
                fbdev->fbvar_new.yres_virtual = h_total;
                fbdev->fbvar_new.xoffset = left_border;
+               fbdev->fbvar_new.yoffset = top_border;
                fbdev->fbvar_new.bits_per_pixel = bpp;
                printf(" switching to %dx%d@%d\n", w, h, bpp);
+
+               // seems to help a bit to avoid glitches
+               vout_fbdev_wait_vsync(fbdev);
+
                ret = ioctl(fbdev->fd, FBIOPUT_VSCREENINFO, &fbdev->fbvar_new);
                if (ret == -1) {
                        perror("FBIOPUT_VSCREENINFO ioctl");
-                       return -1;
+                       return NULL;
                }
+
+               fbdev->buffer_write = 1;
        }
 
        fbdev->buffer_count = buffer_cnt;
@@ -99,6 +107,7 @@ int vout_fbdev_resize(struct vout_fbdev *fbdev, int w, int h, int bpp,
                ret = ioctl(fbdev->fd, FBIOPUT_VSCREENINFO, &fbdev->fbvar_new);
                if (ret == -1) {
                        fbdev->buffer_count = 1;
+                       fbdev->buffer_write = 0;
                        fprintf(stderr, "Warning: failed to increase virtual resolution, "
                                        "doublebuffering disabled\n");
                }
@@ -110,7 +119,7 @@ int vout_fbdev_resize(struct vout_fbdev *fbdev, int w, int h, int bpp,
 
        mem_size = fbdev->fb_size * fbdev->buffer_count;
        if (fbdev->mem_size >= mem_size)
-               return 0;
+               goto out;
 
        if (fbdev->mem != NULL)
                munmap(fbdev->mem, fbdev->mem_size);
@@ -126,11 +135,13 @@ int vout_fbdev_resize(struct vout_fbdev *fbdev, int w, int h, int bpp,
                fbdev->mem = NULL;
                fbdev->mem_size = 0;
                perror("mmap framebuffer");
-               return -1;
+               return NULL;
        }
 
        fbdev->mem_size = mem_size;
-       return 0;
+
+out:
+       return (char *)fbdev->mem + fbdev->fb_size * fbdev->buffer_write;
 }
 
 void vout_fbdev_clear(struct vout_fbdev *fbdev)
@@ -160,6 +171,7 @@ struct vout_fbdev *vout_fbdev_init(const char *fbdev_name, int *w, int *h, int b
 {
        struct vout_fbdev *fbdev;
        int req_w, req_h;
+       void *pret;
        int ret;
 
        fbdev = calloc(1, sizeof(*fbdev));
@@ -188,8 +200,8 @@ struct vout_fbdev *vout_fbdev_init(const char *fbdev_name, int *w, int *h, int b
        if (*h != 0)
                req_h = *h;
 
-       ret = vout_fbdev_resize(fbdev, req_w, req_h, bpp, 0, 0, 0, 0, buffer_cnt);
-       if (ret != 0)
+       pret = vout_fbdev_resize(fbdev, req_w, req_h, bpp, 0, 0, 0, 0, buffer_cnt);
+       if (pret == NULL)
                goto fail;
 
        printf("%s: %ix%i@%d\n", fbdev_name, fbdev->fbvar_new.xres, fbdev->fbvar_new.yres,

diff --git a/platform/linux/fbdev.h b/platform/linux/fbdev.h
index ddbfdab..2db9163 100644 (file)
--- a/platform/linux/fbdev.h
+++ b/platform/linux/fbdev.h
@@ -3,7 +3,7 @@ struct vout_fbdev;
 struct vout_fbdev *vout_fbdev_init(const char *fbdev_name, int *w, int *h, int bpp, int buffer_count);
 void *vout_fbdev_flip(struct vout_fbdev *fbdev);
 void  vout_fbdev_wait_vsync(struct vout_fbdev *fbdev);
-int   vout_fbdev_resize(struct vout_fbdev *fbdev, int w, int h, int bpp,
+void *vout_fbdev_resize(struct vout_fbdev *fbdev, int w, int h, int bpp,
                        int left_border, int right_border, int top_border, int bottom_border,
                        int buffer_count);
 void  vout_fbdev_clear(struct vout_fbdev *fbdev);