Right mouse clicking on two of the preview states in the timeline canvas shown in Figure 2.9 will pop up two Drawable Info Boxes for the preview states. They are displayed in Figure 3.17. The popup Info Box's upper-left-hand corner will be positioned at exactly where right mouse click is detected, and a green line marker will appear on the canvas to indicate what time has been clicked, in case the dialog box is moved from its original popup location. To illustrate what information is presented by the Drawable Info Box, we take the highlighted Drawable Info Box in Figure 3.17 as an example. The Drawable Info Box for the preview state contains a pink label ``Preview State'', and the icon inside the dialog box shows the color and shape of the drawable. Below the icon is a big text area that prints all the detailed statistical information about this preview state. There are six timestamps in the text area: maximum duration, minimum starttime, maximum endtime, average duration, average starttime, and average endtime. Here ``[0]'' refers to starting point, and ``[1]'' refers to the ending point. The three ``average'' timestamps are averaged over all the real drawables represented by this preview drawable. Besides timestamps, the info box also tells the``Number of Real Drawables'' represented by the preview object. In this case, 136 real states are amalgamated by the pure white preview state. Also, the text area lists all the categories of real drawables amalgamated and their ratios of the total duration of all real drawables to the duration of the preview states. In this case, there is only one category of real states in the preview state, so the 136 states are all PACKs. The sum of the durations of all PACKs is about half of the duration of the preview state, as indicated by ``ratio=0.5021433''.
Another Drawable Info Box, shown in Figure 3.17, has its upper left hand pointed at a preview state that has four different strips of colors: yellow, royal blue, white, and purple. Right mouse clicking at the yellow strip pops up a Drawable Info Box with a yellow state icon with label BARRIER. As shown in the figure, this preview state amalgamated four categories of real states: ALLREDUCE, PACK, SSEND, and BARRIER; the statistically most significant one is BARRIER. It proportionally and exclusively occupies 55% of the length of the preview state. Hence the BARRIER strip is the tallest of all the color strips shown in the preview state. Clicking on a different color strip in the same preview state will pop up a drawable info box with a differently labeled icon, but the contents of the text area remains the same. In general, not every category listed in the text area is visible in the preview state display. Of the four categories mentioned in the text area, only three are visible noticeably in the figure given the limited pixel height available to the preview state. The least significant category ALLREDUCE is barely visible. But the limitation can be improved by selecting another display option for the preview state in the Preference window that does not rely on the category ratio3.5. As indicated, there are 58 real drawables in the preview state, but no information is provided about how many real drawables are in each real category.
