Opentk/Source/OpenTK/OpenGL/GLHelper.cs
2008-01-23 00:20:02 +00:00

772 lines
29 KiB
C#

#region --- License ---
/* Copyright (c) 2006-2008 the OpenTK team.
* See license.txt for license info
*
* Contributions by Andy Gill.
*/
#endregion
#region --- Using Directives ---
using System;
using System.Collections.Generic;
using System.Text;
using System.Runtime.InteropServices;
using System.Reflection;
using System.Diagnostics;
using System.Reflection.Emit;
using OpenTK.Math;
using OpenTK.OpenGL.Enums;
#endregion
[assembly: CLSCompliant(true)]
namespace OpenTK.OpenGL
{
/// <summary>
/// OpenGL binding for .NET, implementing OpenGL 2.1, plus extensions.
/// </summary>
/// <remarks>
/// <para>
/// This class contains all OpenGL enums and functions defined in the 2.1 specification.
/// The official .spec files can be found at: http://opengl.org/registry/.
/// </para>
/// <para> A valid OpenGL context must be created before calling any OpenGL function.</para>
/// <para>
/// Use the GL.Load and GL.LoadAll methods to prepare function entry points prior to use. To maintain
/// cross-platform compatibility, this must be done for both core and extension functions. The GameWindow
/// and the GLControl class will take care of this automatically.
/// </para>
/// <para>
/// You can use the GL.SupportsExtension method to check whether any given category of extension functions
/// exists in the current OpenGL context. Keep in mind that different OpenGL contexts may support different
/// extensions, and under different entry points. Always check if all required extensions are still supported
/// when changing visuals or pixel formats.
/// </para>
/// <para>
/// You may retrieve the entry point for an OpenGL function using the GL.GetDelegate method.
/// </para>
/// </remarks>
/// <see href="http://opengl.org/registry/"/>
/// <seealso cref="GL.SupportsExtension"/>
/// <seealso cref="GL.GetDelegate"/>
/// <seealso cref="GL.LoadAll"/>
/// <seealso cref="GL.Load"/>
public static partial class GL
{
delegate void VoidGLDelegate(object @class, object[] parameters);
delegate object ObjectGLDelegate(object @class, object[] parameters);
#region --- Fields ---
internal const string Library = "opengl32.dll";
static StringBuilder sb = new StringBuilder();
static object gl_lock = new object();
private static SortedList<string, bool> AvailableExtensions = new SortedList<string, bool>();
private static bool rebuildExtensionList;
private static Type glClass;
private static Type delegatesClass;
private static Type importsClass;
#endregion
#region --- Constructor ---
static GL()
{
glClass = typeof(GL);
delegatesClass = glClass.GetNestedType("Delegates", BindingFlags.Static | BindingFlags.NonPublic);
importsClass = glClass.GetNestedType("Imports", BindingFlags.Static | BindingFlags.NonPublic);
}
#endregion
#region --- Imports ---
internal static partial class Imports
{
internal static SortedList<string, MethodInfo> FunctionMap; // This is faster than either Dictionary or SortedDictionary
static Imports()
{
MethodInfo[] methods = importsClass.GetMethods(BindingFlags.Static | BindingFlags.NonPublic);
FunctionMap = new SortedList<string, MethodInfo>(methods.Length);
foreach (MethodInfo m in methods)
{
FunctionMap.Add(m.Name, m);
}
}
}
#endregion
#region --- Public Methods ---
#region public static bool SupportsExtension(string name)
/// <summary>
/// Determines whether the specified OpenGL extension category is available in
/// the current OpenGL context. Equivalent to IsExtensionSupported(name, true)
/// </summary>
/// <param name="name">The string for the OpenGL extension category (eg. "GL_ARB_multitexture")</param>
/// <returns>True if the specified extension is available, false otherwise.</returns>
public static bool SupportsExtension(string name)
{
if (rebuildExtensionList)
BuildExtensionList();
lock (gl_lock)
{
sb.Remove(0, sb.Length);
if (!name.StartsWith("GL_"))
sb.Append("gl_");
sb.Append(name.ToLower());
// Search the cache for the string.
return AvailableExtensions.ContainsKey(sb.ToString());
}
}
#endregion
#region public static Delegate GetDelegate(string name)
/// <summary>
/// Returns a System.Delegate wrapping the specified OpenGL function. You must use the
/// base OpenGL name of the function (e.g. "glVertex3fv" instead of "Vertex3").
/// </summary>
/// <param name="name">The name of the OpenGL function (eg. "glNewList")</param>
/// <param name="signature">The signature of the OpenGL function.</param>
/// <returns>
/// A System.Delegate that can be used to call this OpenGL function or null, if the specified
/// function name does not correspond to an OpenGL function or if the function is not
/// supported by the video drivers.
/// </returns>
public static Delegate GetDelegate(string name)
{
FieldInfo info = typeof(Delegates).GetField(name, BindingFlags.Static | BindingFlags.NonPublic);
if (info == null)
return null;
return (Delegate)info.GetValue(null);
}
#endregion
#region public static Delegate GetDelegate(string name, Type signature)
/// <summary>
/// Returns a System.Delegate wrapping an OpenGL function.
/// </summary>
/// <param name="name">The name of the OpenGL function (eg. "glNewList")</param>
/// <param name="signature">The signature of the OpenGL function.</param>
/// <returns>
/// A System.Delegate that can be used to call this OpenGL function, or null if the specified
/// function name did not correspond to an OpenGL function.
/// </returns>
[Obsolete("Use GetDelegate(string name) instead.")]
public static Delegate GetDelegate(string name, Type signature)
{
return LoadDelegate(name, signature);
}
#endregion
#region public static void LoadAll()
/// <summary>
/// Loads all OpenGL functions (core and extensions).
/// </summary>
/// <remarks>
/// <para>
/// This function will be automatically called the first time you use any opengl function. There is
/// </para>
/// <para>
/// Call this function manually whenever you need to update OpenGL entry points.
/// This need may arise if you change the pixelformat/visual, or in case you cannot
/// (or do not want) to use the automatic initialization of the GL class.
/// </para>
/// </remarks>
public static void LoadAll()
{
//TODO: Route GameWindow context creation through GLContext.
//if (GLContext.CurrentContext == null)
// throw new InvalidOperationException("You must create an OpenGL context before using the GL class.");
OpenTK.Platform.Utilities.LoadExtensions(glClass);
}
#endregion
#region public static bool Load(string function)
/// <summary>
/// Tries to reload the given OpenGL function (core or extension).
/// </summary>
/// <param name="name">The name of the OpenGL function (i.e. glShaderSource)</param>
/// <returns>True if the function was found and reloaded, false otherwise.</returns>
/// <remarks>
/// <para>
/// Use this function if you require greater granularity when loading OpenGL entry points.
/// </para>
/// <para>
/// While the automatic initialisation will load all OpenGL entry points, in some cases
/// the initialisation can take place before an OpenGL Context has been established.
/// In this case, use this function to load the entry points for the OpenGL functions
/// you will need, or use ReloadFunctions() to load all available entry points.
/// </para>
/// <para>
/// This function returns true if the given OpenGL function is supported, false otherwise.
/// </para>
/// <para>
/// To query for supported extensions use the IsExtensionSupported() function instead.
/// </para>
/// </remarks>
public static bool Load(string function)
{
FieldInfo f = delegatesClass.GetField(function, BindingFlags.Static | BindingFlags.NonPublic);
if (f == null)
return false;
Delegate old = f.GetValue(null) as Delegate;
Delegate @new = LoadDelegate(f.Name, f.FieldType);
if (old.Target != @new.Target)
{
f.SetValue(null, @new);
rebuildExtensionList = true;
}
return @new != null;
}
#endregion
#region static Delegate LoadDelegate(string name, Type signature)
/// <private />
/// <summary>
/// Loads an OpenGL function into a type-safe System.Delegate.
/// </summary>
/// <param name="name">The name of the OpenGL function (eg. "glNewList")</param>
/// <param name="signature">The signature of the OpenGL function.</param>
/// <returns>
/// A System.Delegate that can be used to call this OpenGL function, or null if the specified
/// function name did not correspond to an OpenGL function.
/// </returns>
static Delegate LoadDelegate(string name, Type signature)
{
MethodInfo m;
return
GetExtensionDelegate(name, signature) ??
/*((m = importsClass.GetMethod(name.Substring(2), BindingFlags.Static | BindingFlags.NonPublic)) != null ?*/
(Imports.FunctionMap.TryGetValue((name.Substring(2)), out m) ?
Delegate.CreateDelegate(signature, m) : null);
}
#endregion
#region public static bool SupportsFunction(string function)
/// <summary>
/// Checks if a given OpenGL function is supported by the current context
/// </summary>
/// <param name="function">The name of the OpenGL function (i.e. glShaderSource)</param>
/// <returns>True if the function is supported, false otherwise</returns>
public static bool SupportsFunction(string function)
{
lock (gl_lock)
{
if (function == null)
throw new ArgumentNullException("function");
sb.Remove(0, sb.Length);
if (!function.StartsWith("gl"))
sb.Append("gl");
sb.Append(function);
FieldInfo f = delegatesClass.GetField(sb.ToString(), BindingFlags.Static | BindingFlags.NonPublic);
if (f == null)
return false;
return f.GetValue(null) != null;
}
}
#endregion
#region public static bool SupportsFunction(string function, string extension)
/// <summary>
/// Checks if a given OpenGL function is supported by the current context
/// </summary>
/// <param name="function">The name of the OpenGL function (e.g. glShaderSource)</param>
/// <param name="extension">The name of the extension catagory (e.g. ARB, EXT, ATI, ...)</param>
/// <returns>True if the function is supported, false otherwise</returns>
public static bool SupportsFunction(string function, string extension)
{
lock (gl_lock)
{
if (function == null)
throw new ArgumentNullException("function");
if (extension == null)
throw new ArgumentNullException("extension");
sb.Remove(0, sb.Length);
if (!function.StartsWith("gl"))
sb.Append("gl");
sb.Append(function);
if (!function.EndsWith(extension))
sb.Append(extension);
FieldInfo f = delegatesClass.GetField(sb.ToString(), BindingFlags.Static | BindingFlags.NonPublic);
if (f == null)
return false;
return f.GetValue(null) != null;
}
}
#endregion
#region public static bool SupportsFunction(Type function)
/// <summary>
/// Checks if a given OpenGL function is supported by the current context
/// </summary>
/// <param name="function">The name of the OpenGL function (e.g. glShaderSource)</param>
/// <param name="extension">The name of the extension catagory (e.g. ARB, EXT, ATI, ...)</param>
/// <returns>True if the function is supported, false otherwise</returns>
public static bool SupportsFunction(MethodInfo method)
{
lock (gl_lock)
{
/*
if (function == null)
throw new ArgumentNullException("function");
sb.Remove(0, sb.Length);
if (!function.Name.StartsWith("gl"))
sb.Append("gl");
sb.Append(function);
//if (!function.EndsWith(extension))
// sb.Append(extension);
FieldInfo f = delegatesClass.GetField(sb.ToString(), BindingFlags.Static | BindingFlags.NonPublic);
if (f == null)
return false;
return f.GetValue(null) != null;
*/
return false;
}
}
#endregion
#region private static void BuildExtensionList()
/// <summary>
/// Builds a cache of the supported extensions to speed up searches.
/// </summary>
private static void BuildExtensionList()
{
// Assumes there is an opengl context current.
AvailableExtensions.Clear();
string version_string = GL.GetString(StringName.Version);
if (String.IsNullOrEmpty(version_string))
{
throw new ApplicationException("Failed to build extension list. Is there an opengl context current?");
}
string version;
// Most drivers return the version in the 3 first characters of the version string,
// (e.g. on Ati X1950 with Catalyst 7.10 -> "2.0.6956 Release"). However, Mesa seems
// to do something strange: "1.4 (2.1 Mesa 7.0.1).".
// We'll do some trickery to get the second number (2.1), but this may break on
// some implementations...
if (version_string.ToLower().Contains("mesa"))
{
int index = version_string.IndexOf('(');
if (index != -1)
version = version_string.Substring(index + 1, 3);
else
version = version_string.TrimStart(' ');
}
else
version = version_string.TrimStart(' ');
Debug.Print(version);
if (version.StartsWith("1.2"))
{
AvailableExtensions.Add("gl_version_1_1", true);
AvailableExtensions.Add("gl_version_1_2", true);
}
else if (version.StartsWith("1.3"))
{
AvailableExtensions.Add("gl_version_1_1", true);
AvailableExtensions.Add("gl_version_1_2", true);
AvailableExtensions.Add("gl_version_1_3", true);
}
else if (version.StartsWith("1.4"))
{
AvailableExtensions.Add("gl_version_1_1", true);
AvailableExtensions.Add("gl_version_1_2", true);
AvailableExtensions.Add("gl_version_1_3", true);
AvailableExtensions.Add("gl_version_1_4", true);
}
else if (version.StartsWith("1.5"))
{
AvailableExtensions.Add("gl_version_1_1", true);
AvailableExtensions.Add("gl_version_1_2", true);
AvailableExtensions.Add("gl_version_1_3", true);
AvailableExtensions.Add("gl_version_1_4", true);
AvailableExtensions.Add("gl_version_1_5", true);
}
else if (version.StartsWith("2.0"))
{
AvailableExtensions.Add("gl_version_1_1", true);
AvailableExtensions.Add("gl_version_1_2", true);
AvailableExtensions.Add("gl_version_1_3", true);
AvailableExtensions.Add("gl_version_1_4", true);
AvailableExtensions.Add("gl_version_1_5", true);
AvailableExtensions.Add("gl_version_2_0", true);
}
else if (version.StartsWith("2.1"))
{
AvailableExtensions.Add("gl_version_1_1", true);
AvailableExtensions.Add("gl_version_1_2", true);
AvailableExtensions.Add("gl_version_1_3", true);
AvailableExtensions.Add("gl_version_1_4", true);
AvailableExtensions.Add("gl_version_1_5", true);
AvailableExtensions.Add("gl_version_2_0", true);
AvailableExtensions.Add("gl_version_2_1", true);
}
string extension_string = GL.GetString(Enums.StringName.Extensions);
if (String.IsNullOrEmpty(extension_string))
return; // no extensions are available
string[] extensions = extension_string.Split(new char[] { ' ' }, StringSplitOptions.RemoveEmptyEntries);
foreach (string ext in extensions)
AvailableExtensions.Add(ext.ToLower(), true);
foreach (string s in AvailableExtensions.Keys)
Debug.Print(s);
rebuildExtensionList = false;
}
#endregion
#endregion
#region --- GetProcAddress ---
private static IGetProcAddress getProcAddress;
internal interface IGetProcAddress
{
IntPtr GetProcAddress(string function);
}
internal class GetProcAddressWindows : IGetProcAddress
{
[System.Runtime.InteropServices.DllImport(Library, EntryPoint = "wglGetProcAddress", ExactSpelling = true)]
private static extern IntPtr wglGetProcAddress(String lpszProc);
public IntPtr GetProcAddress(string function)
{
return wglGetProcAddress(function);
}
}
internal class GetProcAddressX11 : IGetProcAddress
{
[DllImport(Library, EntryPoint = "glXGetProcAddress")]
private static extern IntPtr glxGetProcAddress([MarshalAs(UnmanagedType.LPTStr)] string procName);
public IntPtr GetProcAddress(string function)
{
return glxGetProcAddress(function);
}
}
internal class GetProcAddressOSX : IGetProcAddress
{
private const string Library = "libdl.dylib";
[DllImport(Library, EntryPoint = "NSIsSymbolNameDefined")]
private static extern bool NSIsSymbolNameDefined(string s);
[DllImport(Library, EntryPoint = "NSLookupAndBindSymbol")]
private static extern IntPtr NSLookupAndBindSymbol(string s);
[DllImport(Library, EntryPoint = "NSAddressOfSymbol")]
private static extern IntPtr NSAddressOfSymbol(IntPtr symbol);
public IntPtr GetProcAddress(string function)
{
string fname = "_" + function;
if (!NSIsSymbolNameDefined(fname))
return IntPtr.Zero;
IntPtr symbol = NSLookupAndBindSymbol(fname);
if (symbol != IntPtr.Zero)
symbol = NSAddressOfSymbol(symbol);
return symbol;
}
}
#region private static IntPtr GetAddress(string function)
/// <summary>
/// Retrieves the entry point for a dynamically exported OpenGL function.
/// </summary>
/// <param name="name">The function string for the OpenGL function (eg. "glNewList")</param>
/// <returns>
/// An IntPtr contaning the address for the entry point, or IntPtr.Zero if the specified
/// OpenGL function is not dynamically exported.
/// </returns>
/// <remarks>
/// <para>
/// The Marshal.GetDelegateForFunctionPointer method can be used to turn the return value
/// into a call-able delegate.
/// </para>
/// <para>
/// This function is cross-platform. It determines the underlying platform and uses the
/// correct wgl, glx or agl GetAddress function to retrieve the function pointer.
/// </para>
/// <see cref="Marshal.GetDelegateForFunctionPointer"/>
/// <seealso cref="Gl.GetDelegateForExtensionMethod"/>
/// </remarks>
private static IntPtr GetAddress(string function)
{
if (getProcAddress == null)
{
if (System.Environment.OSVersion.Platform == PlatformID.Win32NT ||
System.Environment.OSVersion.Platform == PlatformID.Win32S ||
System.Environment.OSVersion.Platform == PlatformID.Win32Windows ||
System.Environment.OSVersion.Platform == PlatformID.WinCE)
{
getProcAddress = new GetProcAddressWindows();
}
else if (System.Environment.OSVersion.Platform == PlatformID.Unix)
{
getProcAddress = new GetProcAddressX11();
}
else
{
throw new PlatformNotSupportedException(
"Extension loading is only supported under X11 and Windows. We are sorry for the inconvience.");
}
}
return getProcAddress.GetProcAddress(function);
}
#endregion
#region internal static Delegate GetExtensionDelegate(string name, Type signature)
/// <summary>
/// Creates a System.Delegate that can be used to call a dynamically exported OpenGL function.
/// </summary>
/// <param name="name">The name of the OpenGL function (eg. "glNewList")</param>
/// <param name="signature">The signature of the OpenGL function.</param>
/// <returns>
/// A System.Delegate that can be used to call this OpenGL function or null
/// if the function is not available in the current OpenGL context.
/// </returns>
internal static Delegate GetExtensionDelegate(string name, Type signature)
{
IntPtr address = GetAddress(name);
if (address == IntPtr.Zero ||
address == new IntPtr(1) || // Workaround for buggy nvidia drivers which return
address == new IntPtr(2)) // 1 or 2 instead of IntPtr.Zero for some extensions.
{
return null;
}
else
{
return Marshal.GetDelegateForFunctionPointer(address, signature);
}
}
#endregion
#endregion
#region --- GL Overloads ---
#region public static void Color[34]() overloads
public static void Color3(System.Drawing.Color color)
{
GL.Color3(color.R, color.G, color.B);
}
public static void Color4(System.Drawing.Color color)
{
GL.Color4(color.R, color.G, color.B, color.A);
}
public static void Color3(Vector3 color)
{
GL.Color3(color.X, color.Y, color.Z);
}
public static void Color4(Vector4 color)
{
GL.Color4(color.X, color.Y, color.Z, color.W);
}
#endregion
#region public static void ClearColor() overloads
public static void ClearColor(System.Drawing.Color color)
{
GL.ClearColor(color.R/255.0f, color.G/255.0f, color.B/255.0f, color.A/255.0f);
}
#endregion
#region overloads using OpenTK.Math classes
public static void Normal3(Vector3 normal)
{
Delegates.glNormal3f(normal.X, normal.Y, normal.Z);
}
public static void RasterPos2(Vector2 pos)
{
Delegates.glRasterPos2f(pos.X, pos.Y);
}
public static void RasterPos3(Vector3 pos)
{
Delegates.glRasterPos3f(pos.X, pos.Y, pos.Z);
}
public static void RasterPos4(Vector4 pos)
{
Delegates.glRasterPos4f(pos.X, pos.Y, pos.Z, pos.W);
}
public static void Vertex2(Vector2 v)
{
Delegates.glVertex2f(v.X, v.Y);
}
public static void Vertex3(Vector3 v)
{
Delegates.glVertex3f(v.X, v.Y, v.Z);
}
public static void Vertex4(Vector4 v)
{
Delegates.glVertex4f(v.X, v.Y, v.Z, v.W);
}
public static void TexCoord2(Vector2 v)
{
Delegates.glTexCoord2f(v.X, v.Y);
}
public static void TexCoord3(Vector3 v)
{
Delegates.glTexCoord3f(v.X, v.Y, v.Z);
}
public static void TexCoord4(Vector4 v)
{
Delegates.glTexCoord4f(v.X, v.Y, v.Z, v.W);
}
public static void Rotate(Single angle, Vector3 axis)
{
Delegates.glRotatef((Single)angle, axis.X, axis.Y, axis.Z);
}
public static void Scale(Vector3 scale)
{
Delegates.glScalef(scale.X, scale.Y, scale.Z);
}
public static void Translate(Vector3 trans)
{
Delegates.glTranslatef(trans.X, trans.Y, trans.Z);
}
public static void MultMatrix(Matrix4 mat)
{
MultMatrix(ref mat.Row0.X);
}
public static void Materialv(MaterialFace face, MaterialParameter pname, Vector4 @params)
{
unsafe
{
Materialv(face, pname, &@params.X);
}
}
#endregion
#region public static void ShaderSource(Int32 shader, System.String @string)
public static void ShaderSource(Int32 shader, System.String @string)
{
unsafe
{
int length = @string.Length;
Delegates.glShaderSource((UInt32)shader, 1, new string[] { @string }, &length);
}
}
#endregion
#region public static void GetShaderInfoLog(Int32 shader, out string info)
public static void GetShaderInfoLog(Int32 shader, out string info)
{
unsafe
{
int length;
GL.GetShader(shader, ShaderParameter.InfoLogLength, out length);
if (length == 0)
{
info = "";
return;
}
StringBuilder sb = new StringBuilder(length);
Delegates.glGetShaderInfoLog((UInt32)shader, sb.Capacity, &length, sb);
info = sb.ToString();
}
}
#endregion
#region public static void PointParameter(PointSpriteCoordOriginParameter param)
/// <summary>
/// Helper function that defines the coordinate origin of the Point Sprite.
/// </summary>
/// <param name="param">
/// A OpenTK.OpenGL.GL.PointSpriteCoordOriginParameter token,
/// denoting the origin of the Point Sprite.
/// </param>
public static void PointParameter(PointSpriteCoordOriginParameter param)
{
GL.PointParameter(PointParameterName.PointSpriteCoordOrigin, (int)param);
}
#endregion
#endregion
}
}