Hash :
050b124d
Author :
Date :
2019-06-30T03:26:18
Reland "Vulkan: Debug overlay" This is a reland of e54d0f90d1a165404236fd7abd1b05ddd041a686 This was reverted due to a build failure as a result of a missing virtual destructor in the widget base class. Original change's description: > Vulkan: Debug overlay > > A debug overlay system for the Vulkan backend designed with efficiency > and runtime configurability in mind. Overlay widgets are of two > fundamental types: > > - Text widgets: A single line of text with small, medium or large font. > - Graph widgets: A bar graph of data. > > Built on these, various overlay widget types are defined that gather > statistics. Five such types are defined with one widget per type as > example: > > - Count: A widget that counts something. VulkanValidationMessageCount > is an overlay widget of this type that shows the number of validation > messages received from the validation layers. > - Text: A generic text. VulkanLastValidationMessage is an overlay > widget of this type that shows the last validation message. > - PerSecond: A value that gets reset every second automatically. FPS is > an overlay widget of this type that simply gets incremented on every > swap(). > - RunningGraph: A graph of last N values. VulkanCommandGraphSize is an > overlay of this type. On every vkQueueSubmit, the number of nodes in > the command graph is accumulated. On every present(), the value is > taken as the number of nodes for the whole duration of the frame. > - RunningHistogram: A histogram of last N values. Input values are in > the [0, 1] range and they are ranked to N buckets for histogram > calculation. VulkanSecondaryCommandBufferPoolWaste is an overlay > widget of this type. On vkQueueSubmit, the memory waste from command > buffer pool allocations is recorded in the histogram. > > Overlay font is placed in libANGLE/overlay/ which gen_overlay_fonts.py > processes to create an array of bits, which is processed at runtime to > create the actual font image (an image with 3 layers). > > The overlay widget layout is defined in overlay_widgets.json which > gen_overlay_widgets.py processes to generate an array of widgetss, each > of its respective type, and sets their properties, such as color and > bounding box. The json file allows widgets to align against other > widgets as well as against the framebuffer edges. > > Two compute shaders are implemented to efficiently render the UI: > > - OverlayCull: This shader creates a bitset of Text and Graph widgets > whose bounding boxes intersect a corresponding subgroup processed by > OverlayDraw. This is done only when the enabled overlay widgets are > changed (a feature that is not yet implemented) or the surface is > resized. > - OverlayDraw: Using the bitsets generated by OverlayCull, values that > are uniform for each workgroup (set to be equal to hardware subgroup > size), this shader loops over enabled widgets that can possibly > intersect the pixel being processed and renders and blends in texts > and graphs. This is done once per frame on present(). > > Currently, to enable overlay widgets an environment variable is used. > For example: > > $ export ANGLE_OVERLAY=FPS:VulkanSecondaryCommandBufferPoolWaste > $ ./hello_triangle --use-angle=vulkan > > Possible future work: > > - On Android, add settings in developer options and enable widgets based > on those. > - Spawn a small server in ANGLE and write an application that sends > enable/disable commands remotely. > - Implement overlay for other backends. > > Bug: angleproject:3757 > Change-Id: If9c6974d1935c18f460ec569e79b41188bd7afcc > Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/1729440 > Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org> > Reviewed-by: Jamie Madill <jmadill@chromium.org> Bug: angleproject:3757 Change-Id: I47915d88b37b6f882c686c2de13fca309a10b572 Reviewed-on: https://chromium-review.googlesource.com/c/angle/angle/+/1780897 Reviewed-by: Jamie Madill <jmadill@chromium.org> Commit-Queue: Shahbaz Youssefi <syoussefi@chromium.org>