OpenGL is a cross-platform graphics API that specifies a standard software interface for 3D graphics processing hardware. A device running Android 4. This topic focuses on the Android framework interfaces. If your goal is to use OpenGL in your Android application, understanding how to implement these classes in an activity should be your first objective. The GLSurfaceView. Renderer interface requires that you implement the following methods:.
If your application uses OpenGL features that are not available on all devices, you must include these requirements in your AndroidManifest. Here are the most common OpenGL manifest declarations:. Adding this declaration causes Google Play to restrict your application from being installed on devices that do not support OpenGL ES 2.
Declaring texture compression requirements in your manifest hides your application from users with devices that do not support at least one of your declared compression types. One of the basic problems in displaying graphics on Android devices is that their screens can vary in size and shape. OpenGL assumes a square, uniform coordinate system and, by default, happily draws those coordinates onto your typically non-square screen as if it is perfectly square.
Figure 1. Default OpenGL coordinate system left mapped to a typical Android device screen right. The illustration above shows the uniform coordinate system assumed for an OpenGL frame on the left, and how these coordinates actually map to a typical device screen in landscape orientation on the right.
To solve this problem, you can apply OpenGL projection modes and camera views to transform coordinates so your graphic objects have the correct proportions on any display. In order to apply projection and camera views, you create a projection matrix and a camera view matrix and apply them to the OpenGL rendering pipeline. The projection matrix recalculates the coordinates of your graphics so that they map correctly to Android device screens. The camera view matrix creates a transformation that renders objects from a specific eye position.
In the ES 1. In the ES 2. With this matrix member added, you can then generate and apply projection and camera viewing matrices to your objects. Note: The example above defines a single transformation matrix member in the vertex shader into which you apply a combined projection matrix and camera view matrix. Depending on your application requirements, you may want to define separate projection matrix and camera viewing matrix members in your vertex shaders so you can change them independently.
In OpenGL, the face of a shape is a surface defined by three or more points in three-dimensional space. A set of three or more three-dimensional points called vertices in OpenGL have a front face and a back face. How do you know which face is front and which is the back? Good question. The answer has to do with winding, or, the direction in which you define the points of a shape. Illustration of a coordinate list which translates into a counterclockwise drawing order.Skia is an open source 2D graphics library that provides common APIs that work across a variety of hardware and software platforms.
Although major component engineering is done by the Skia development team, we consider the contributions from any source. TotalCross uses OpenGL in the graphics, but this technology was depreciated in iOS and, to keep up with the constant upgrades and improvements that TotalCross proposes to do on all platforms, we decided that this was the best time to bring a complementary technology and even better to our tool.
That's why Skia was chosen to be implemented. Among the many improvements that the implementation of skia has brought to TotalCross are:. General visual quality. Possibility of using fonts direct from.
Memory Usage Optimization. Easier to improve visual effects in TotalCross internally. TotalCross Platform. TotalCross Overview. TotalCross Javadoc. TotalCross Changelog.
Get Started. Developers Area. SQLite Encryption. Branch workflow. Creating an Issue. IMEI in Android Local Database - SQLite. Writing documentation. Powered by GitBook. Why did we choose skia? Impact of Skia on TotalCross.
Last updated 6 months ago.The Android Emulator can use hardware acceleration features to improve performance, sometimes drastically.
This page describes how you can configure graphics and virtual machine VM acceleration to get higher performance from the emulator. Graphics acceleration uses your computer's hardware typically the GPU to make screen rendering faster. Hardware acceleration is recommended and is typically faster. However, you might need to use software acceleration if your computer uses graphics drivers that aren't compatible with the emulator. By default, the emulator decides whether to use hardware or software graphics acceleration based on your computer setup.
If you start the emulator from the command lineyou can also override the graphics acceleration setting in the AVD for that virtual device instance. To specify a graphics acceleration type when you run an AVD from the command line, include the -gpu option, as shown in the following example:. The value of mode can be set to one of the following options:. The following mode options are deprecated:. Skia helps the emulator render graphics more smoothly and efficiently.
VM acceleration uses your computer's processor to significantly improve the execution speed of the emulator. A tool called a hypervisor manages this interaction using virtualization extensions that your computer's processor provides. This section outlines the requirements for using VM acceleration and describes how to set up VM acceleration on each operating system. To use VM acceleration with the emulator, your computer must meet the general requirements in this section.
Your computer also needs to meet other requirements that are specific to your operating system. In addition to the development environment requirements, your computer's processor must support one of the following virtualization extensions technologies:.
Most modern processors support these virtualization extensions. If you're not sure whether your processor supports these extensions, check the specifications for your processor on the manufacturer's site. If your processor doesn't support one of these extensions, then you can't use VM acceleration. Without a hypervisor and VM acceleration, the emulator must translate the machine code from the VM block by block to conform to the architecture of the host computer.
This process can be quite slow. With a hypervisor, the VM and the architecture of the host computer match, so the emulator can run code directly on the host processor using the hypervisor.
This improvement drastically increases both the speed and performance of the emulator. The hypervisor that will work best for you depends on your computer's operating system and configuration. For more information, see one of the following sections:. You can use the emulator -accel-check command-line option to check if a hypervisor is currently installed on your computer.
The following examples show how to use use the emulator accel-check option. In each example, sdk is the location of the Android SDK:. Quite a few features in Windows 10 will enable Hyper-V implicitly. Users may not even know Hyper-V is activated when they enable one of these features.
This list is not exhaustive, please notify us on our bug tracker if you find an item that should be included here. Double-check that the features listed above are also disabled when disabling Hyper-V.June in General Discussion. Do any of you have experience playing this game with 4x MSAA?
If so, can you tell me how does the game performs under this setting enabled. Have you tried it? Thanks, just want to know what the community have to say. Ricardobalto Posts: June For those who are confused:. AcuTarA oh I've been researching and MSAA is an antialiasing technique that supposedly improves graphic quality in games.
The option in Android forces the game to run with this graphic enhancement, but at a cost of battery life and fps. So unless you are running the game with a Nvidia desktop gpu, best to keep it at default. Maybe it's worth enabling in certain games, but obviously not in this one. The other thing, the opengl gpu render option, setting it to Skia may result in decrease performance in 3D games, because it's a library that specializes in 2D graphics, in comparison to the default one that is more generalized.
Then it is at my understand that both is bad? Yes xD at least for this specific game. DNA Posts: 10, Guardian.
Skia Graphics Engine
Almost every phone has the option you are referring to. Again, xiaomi offer ability to log certain clocks. Sign In or Register to comment.
Ganesh has experimented with two accelerated approaches. The first used the stencil buffer to render paths. Because of API overheads with this approach, this first approach was replaced with a second approach where the CPU-based rasterizer computes a coverage mask which is loaded as a texture upon every path draw to provide the GPU proper antialiased coverage.
This hybrid scheme is often bottlenecked by the dynamic texture updates required for every rendered path. From Wikipedia, the free encyclopedia.
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Namespaces Article Talk. Views Read Edit View history. Help Community portal Recent changes Upload file. Download as PDF Printable version.The Android framework offers a variety of graphics rendering APIs for 2D and 3D that interact with manufacturer implementations of graphics drivers, so it is important to have a good understanding of how those APIs work at a higher level.
This page introduces the graphics hardware abstraction layer HAL upon which those drivers are built. No matter what rendering API developers use, everything is rendered onto a "surface.
Every window that is created on the Android platform is backed by a surface. All of the visible surfaces rendered are composited onto the display by SurfaceFlinger.
An image stream producer can be anything that produces graphic buffers for consumption. The most common consumer of image streams is SurfaceFlinger, the system service that consumes the currently visible surfaces and composites them onto the display using information provided by the Window Manager.
SurfaceFlinger is the only service that can modify the content of the display. Other OpenGL ES apps can consume image streams as well, such as the camera app consuming a camera preview image stream. Non-GL applications can be consumers too, for example the ImageReader class. The hardware abstraction for the display subsystem.
[MODULE] OpenGL (Skia) as Default Renderer
This makes compositing lower power than having the GPU conduct all computation. The Hardware Composer HAL conducts the other half of the work and is the central point for all Android graphics rendering. The graphics memory allocator Gralloc is needed to allocate memory requested by image producers. For details, see Gralloc HAL. The objects on the left are renderers producing graphics buffers, such as the home screen, status bar, and system UI.
SurfaceFlinger is the compositor and Hardware Composer is the composer. BufferQueues provide the glue between the Android graphics components. These are a pair of queues that mediate the constant cycle of buffers from the producer to the consumer.
Once the producers hand off their buffers, SurfaceFlinger is responsible for compositing everything onto the display. BufferQueue contains the logic that ties image stream producers and image stream consumers together. Some examples of image consumers are SurfaceFlinger or another app that displays an OpenGL ES stream, such as the camera app displaying the camera viewfinder. BufferQueue is a data structure that combines a buffer pool with a queue and uses Binder IPC to pass buffers between processes.
The producer interface, or what you pass to somebody who wants to generate graphic buffers, is IGraphicBufferProducer part of SurfaceTexture. BufferQueue can operate in three different modes:. Synchronous-like mode - BufferQueue by default operates in a synchronous-like mode, in which every buffer that comes in from the producer goes out at the consumer. No buffer is ever discarded in this mode. And if the producer is too fast and creates buffers faster than they are being drained, it will block and wait for free buffers.
Non-blocking mode - BufferQueue can also operate in a non-blocking mode where it generates an error rather than waiting for a buffer in those cases. No buffer is ever discarded in this mode either. This is useful for avoiding potential deadlocks in application software that may not understand the complex dependencies of the graphics framework.
Discard mode - Finally, BufferQueue may be configured to discard old buffers rather than generate errors or wait.
The reference docs for these classes are pretty sparse and the docs for Canvas and Paint don't really add any useful explanation. It's also not entirely clear to me how drawing operations that have intrinsic colors eg: drawBitmapversus the "vector" primitives like drawRect fit into all of this -- do they always ignore the Paint 's color and use use their intrinsic color instead? This erases an oval. Before I noticed this my mental-model was that drawing to a canvas conceptually draws to a separate "layer" and then that layer is composed with the Canvas's Bitmap using the Paint's transfer mode.
If it were as simple as that then the above code would erase the entire Bitmap within the clipping region as CLEAR always sets the color and alpha to 0 regardless of the source's alpha. So this implies that there's an additional sort of masking going on to constrain the erasing to an oval.
I did find the API demos but each demo works "in a vacuum" and doesn't show how the thing it focusses on eg: XferModes interacts with other stuff eg: ColorFilters. This question was inspired by seeing the code in this answer to another SO question.
While looking around for some documentation it occurred to me that since much the stuff I'm interested in here seems to be a pretty thin veneer on top of skiamaybe there's some skia documentation that would be helpful. The best thing I could find is the documentation for SkPaint which says:. It isn't stated explicitly, but I'm guessing that the order of the effects here is the order they appear in the pipeline.
There wasn't really any complete documentation, and complete documentation would be kind of large to include here. I ended up reading through the source and doing a bunch of experiments. I took notes along the way, and ended up turning them into a document which you can see here:. The "source colors" come from the Shader. In other cases, if no Shader is specified a Shader that just generates a solid color, the Paint 's color, is used.
The XferMode applies to the "source colors" from the Shader and the "destination colors" from the Canvas 's Bitmap. The result is then blended with the destination using the mask computed in Rasterization. See the Transfer phase in the above document for more details. This question is difficult to answer on StackOverflow. The color information always comes from the Paint object. Your model is a bit off. The oval is not drawn into a separate layer unless you call Canvas.Android Oreo - Moto Maxx - OpenGL ou Skia? [Ajustando o Maxx para jogos]
The Paint's transfer mode is applied to every pixel drawn by the primitive. In this case, only the result of the rasterization of an oval affects the Bitmap. There's no special masking going on, the oval itself is the mask. The pipeline becomes just a little bit more complicated when using layers Canvas. You first go through the pipeline to render your primitive s inside an offscreen bitmap the layerand the offscreen bitmap is then applied to the Canvas by going through the pipeline.