/// <summary>
/// Reallocates the renderbuffer's storage.
/// </summary>
/// <param name="width">The renderbuffer's width in pixels.</param>
/// <param name="height">The renderbuffer's height in pixels.</param>
private void AllocateRenderbufferStorage(Int32 width, Int32 height)
{
using (OpenGLState.ScopedBindRenderbuffer(renderbuffer, true))
{
switch (format)
{
case RenderBufferFormat.Color:
gl.RenderbufferStorage(gl.GL_RENDERBUFFER, gl.IsGLES2 ? gl.GL_RGBA4 : gl.GL_RGBA8, width, height);
gl.ThrowIfError();
break;
case RenderBufferFormat.Depth24Stencil8:
gl.RenderbufferStorage(gl.GL_RENDERBUFFER, gl.GL_DEPTH24_STENCIL8, width, height);
gl.ThrowIfError();
break;
case RenderBufferFormat.Depth32:
gl.RenderbufferStorage(gl.GL_RENDERBUFFER, gl.GL_DEPTH_COMPONENT32, width, height);
gl.ThrowIfError();
break;
case RenderBufferFormat.Depth16:
gl.RenderbufferStorage(gl.GL_RENDERBUFFER, gl.GL_DEPTH_COMPONENT16, width, height);
gl.ThrowIfError();
break;
case RenderBufferFormat.Stencil8:
gl.RenderbufferStorage(gl.GL_RENDERBUFFER, gl.GL_STENCIL_INDEX8, width, height);
break;
default:
throw new NotSupportedException("format");
}
}
}
/// <summary>
/// Initializes a new instance of the <see cref="OpenGLGraphicsCapabilities"/> class.
/// </summary>
/// <param name="configuration">The configuration settings for the Ultraviolet context.</param>
internal unsafe OpenGLGraphicsCapabilities(OpenGLUltravioletConfiguration configuration)
{
this.maximumTextureSize = gl.GetInteger(gl.GL_MAX_TEXTURE_SIZE);
gl.ThrowIfError();
var viewportDims = stackalloc int[2];
gl.GetIntegerv(gl.GL_MAX_VIEWPORT_DIMS, viewportDims);
gl.ThrowIfError();
this.maximumViewportWidth = viewportDims[0];
this.maximumViewportHeight = viewportDims[1];
this.supportsDepthStencilTextures = !gl.IsGLES2 || gl.IsExtensionSupported("GL_OES_packed_depth_stencil");
if (gl.IsGLES2 && !this.supportsDepthStencilTextures)
{
// HACK: Guess what? The Visual Studio Emulator for Android flat-out lies about this.
// So it seems the only reliable way to determine support for depth/stencil is to
// actually try to create one and see if it fails. I hate Android emulators.
var rb = gl.GenRenderbuffer();
using (var state = OpenGLState.ScopedBindRenderbuffer(rb, true))
{
gl.RenderbufferStorage(gl.GL_RENDERBUFFER, gl.GL_DEPTH24_STENCIL8, 32, 32);
this.supportsDepthStencilTextures = (gl.GetError() == gl.GL_NO_ERROR);
}
gl.DeleteRenderBuffers(rb);
}
this.SupportsNonZeroBaseInstance = SupportsInstancedRendering && !gl.IsGLES &&
(gl.IsVersionAtLeast(4, 2) || gl.IsExtensionSupported("GL_ARB_base_instance"));
this.SupportsIndependentSamplerState = (gl.IsGLES ? gl.IsVersionAtLeast(3, 0) : gl.IsVersionAtLeast(3, 3)) ||
gl.IsExtensionSupported("GL_ARB_sampler_objects");
this.SupportsIntegerVertexAttributes = !gl.IsGLES2 || gl.IsExtensionSupported("GL_EXT_gpu_shader4");
this.SupportsDoublePrecisionVertexAttributes = !gl.IsGLES && gl.IsVersionAtLeast(4, 1);
this.SupportsMapBufferRange = true;
if (gl.IsGLES2)
{
this.SupportsMapBufferRange =
gl.IsExtensionSupported("GL_ARB_map_buffer_range") ||
gl.IsExtensionSupported("GL_EXT_map_buffer_range");
}
this.MinMapBufferAlignment = gl.IsExtensionSupported("GL_ARB_map_buffer_alignment") ?
gl.GetInteger(gl.GL_MIN_MAP_BUFFER_ALIGNMENT) : 0;
// There seems to be a bug in the version of Mesa which is distributed
// with Ubuntu 16.04 that causes long stalls when using glMapBufferRange.
// Testing indicates that this is fixed in 11.2.2.
var version = gl.GetString(gl.GL_VERSION);
var versionMatchMesa = Regex.Match(version, "Mesa (?<major>\\d+).(?<minor>\\d+).(?<build>\\d+)");
if (versionMatchMesa != null && versionMatchMesa.Success)
{
var mesaMajor = Int32.Parse(versionMatchMesa.Groups["major"].Value);
var mesaMinor = Int32.Parse(versionMatchMesa.Groups["minor"].Value);
var mesaBuild = Int32.Parse(versionMatchMesa.Groups["build"].Value);
var mesaVersion = new Version(mesaMajor, mesaMinor, mesaBuild);
if (mesaVersion < new Version(11, 2, 2))
{
configuration.UseBufferMapping = false;
}
}
// If we've been explicitly told to disable buffer mapping, override the caps from the driver.
if (!configuration.UseBufferMapping)
{
this.SupportsMapBufferRange = false;
}
}