Opentk/Source/Examples/OpenGL/GLSL/JuliaSetFractal.cs
the_fiddler 6bbaad8bfb Moved and renamed examples to match the new example structurs.
Made example source code visible for all examples in example browser.
Updated Prebuild.exe to newest SVN version (resolves issues with resources).
Added .rtf and .resx files to Examples project in Prebuild.xml.
2009-04-20 09:48:33 +00:00

321 lines
12 KiB
C#

#region --- License ---
/* Licensed under the MIT/X11 license.
* Copyright (c) 2006-2008 the OpenTK Team.
* This notice may not be removed from any source distribution.
* See license.txt for licensing detailed licensing details.
*
* Written by Christoph Brandtner
*/
#endregion
using System;
using System.Windows.Forms;
using System.Diagnostics;
using System.Drawing;
using System.Drawing.Imaging;
using System.IO;
using OpenTK;
using OpenTK.Graphics;
namespace Examples.Tutorial
{
/// <summary>
/// Demonstrates how to render an animated Julia Set in real-time. Quality is sacrificed for speed.
/// Info about the fractal: http://en.wikipedia.org/wiki/Julia_set
/// One more major optimization could be applied (exploit the symmetry of the image with RTT), but
/// that would make the program alot more complicated to follow. You can do this as an exercise.
/// </summary>
[Example("GLSL Animated Julia Set", ExampleCategory.OpenGL, "GLSL", Documentation="JuliaSetFractal.cs")]
public class JuliaSetFractal : GameWindow
{
public JuliaSetFractal()
: base(512, 512)
{
}
#region Private Fields
// GLSL Objects
int VertexShaderObject, FragmentShaderObject, ProgramObject;
int TextureObject;
// Julia Variables for animation
float AnimOffsetX = 0.213f; // using non-zero as starting point to make it more interesting
float AnimOffsetY = 0.63f;
const double AnimSpeedX = 0.65; // anim speed scaling is solely used to make the anim more interesting
const double AnimSpeedY = 1.05;
const double AnimCosinusPercent = 0.85f; // scales the cosinus down to 85% to avoid the (boring) borders
float UniformScaleFactorX; // fractal horizontal scaling is only affected by window resize
float UniformScaleFactorY; // fractal vertical scaling is only affected by window resize
float UniformOffsetX = 1.8f; // fractal horizontal offset
float UniformOffsetY = 1.8f; // fractal vertical offset
// Text drawing (for fps)
TextPrinter printer = new TextPrinter();
Font font = new Font(FontFamily.GenericSansSerif, 16.0f);
#endregion private Fields
#region OnLoad
/// <summary>
/// Setup OpenGL and load resources here.
/// </summary>
/// <param name="e">Not used.</param>
public override void OnLoad(EventArgs e)
{
// Check for necessary capabilities:
if (!GL.SupportsExtension("VERSION_2_0"))
{
MessageBox.Show("You need at least OpenGL 2.0 to run this example. Aborting.",
"GLSL not supported", MessageBoxButtons.OK, MessageBoxIcon.Exclamation);
this.Exit();
}
this.VSync = VSyncMode.On;
GL.Disable(EnableCap.Dither);
GL.ClearColor(0.2f, 0f, 0.4f, 0f);
// declare some variables for tracking which shader did compile, and which texture to use
string[] ShaderFilenames = new string[2];
ShaderFilenames[0] = "Data/Shaders/JuliaSet_SM3_FS.glsl";
ShaderFilenames[1] = "Data/Shaders/JuliaSet_SM2_FS.glsl";
byte CurrentOption = 0;
string LogInfo;
#region Shaders
// Load&Compile Vertex Shader
using (StreamReader sr = new StreamReader("Data/Shaders/JuliaSet_VS.glsl"))
{
VertexShaderObject = GL.CreateShader(ShaderType.VertexShader);
GL.ShaderSource(VertexShaderObject, sr.ReadToEnd());
GL.CompileShader(VertexShaderObject);
}
GL.GetShaderInfoLog(VertexShaderObject, out LogInfo);
if (LogInfo.Length > 0 && !LogInfo.Contains("hardware"))
Trace.WriteLine("Vertex Shader Log:\n" + LogInfo);
else
Trace.WriteLine("Vertex Shader compiled without complaint.");
// Load&Compile Fragment Shader
FragmentShaderObject = GL.CreateShader(ShaderType.FragmentShader);
do
{
using (StreamReader sr = new StreamReader(ShaderFilenames[CurrentOption]))
{
GL.ShaderSource(FragmentShaderObject, sr.ReadToEnd());
GL.CompileShader(FragmentShaderObject);
}
GL.GetShaderInfoLog(FragmentShaderObject, out LogInfo);
if (LogInfo.Length > 0 && !LogInfo.Contains("hardware"))
Trace.WriteLine("Compiling " + ShaderFilenames[CurrentOption] + " failed!\nLog:\n" + LogInfo);
else
{
Trace.WriteLine("Fragment Shader compiled without complaint.");
break;
}
if (++CurrentOption > 1)
{
MessageBox.Show("Neither SM2 nor SM3 Fragment Shader compiled successfully. Aborting.",
"Fatal Error", MessageBoxButtons.OK, MessageBoxIcon.Error);
this.Exit();
}
} while (true);
// Link the Shaders to a usable Program
ProgramObject = GL.CreateProgram();
GL.AttachShader(ProgramObject, VertexShaderObject);
GL.AttachShader(ProgramObject, FragmentShaderObject);
GL.LinkProgram(ProgramObject);
// make current
GL.UseProgram(ProgramObject);
// Flag ShaderObjects for delete when app exits
GL.DeleteShader(VertexShaderObject);
GL.DeleteShader(FragmentShaderObject);
#endregion Shaders
#region Textures
// Load&Bind the 1D texture for color lookups
GL.ActiveTexture(TextureUnit.Texture0); // select TMU0
GL.GenTextures(1, out TextureObject);
GL.TexParameter(TextureTarget.Texture1D, TextureParameterName.TextureMagFilter, (int)TextureMagFilter.Linear);
GL.TexParameter(TextureTarget.Texture1D, TextureParameterName.TextureMinFilter, (int)TextureMinFilter.Linear);
GL.TexParameter(TextureTarget.Texture1D, TextureParameterName.TextureWrapS, (int)(TextureWrapMode)All.ClampToEdge);
using (Bitmap bitmap = new Bitmap("Data/JuliaColorTable.bmp"))
{
BitmapData data = bitmap.LockBits(new Rectangle(0, 0, bitmap.Width, bitmap.Height), ImageLockMode.ReadOnly,
System.Drawing.Imaging.PixelFormat.Format24bppRgb);
GL.TexImage1D(TextureTarget.Texture1D, 0, PixelInternalFormat.Rgb8, data.Width, 0, OpenTK.Graphics.PixelFormat.Bgr,
PixelType.UnsignedByte, data.Scan0);
bitmap.UnlockBits(data);
}
#endregion Textures
Keyboard.KeyUp += KeyUp;
}
int i = 0;
void KeyUp(OpenTK.Input.KeyboardDevice sender, OpenTK.Input.Key e)
{
if (e == OpenTK.Input.Key.F12)
{
Bitmap bmp = new Bitmap(this.Width, this.Height);
System.Drawing.Imaging.BitmapData data =
bmp.LockBits(new Rectangle(0, 0, this.Width, this.Height),
System.Drawing.Imaging.ImageLockMode.WriteOnly,
System.Drawing.Imaging.PixelFormat.Format24bppRgb);
GL.ReadPixels(0, 0, this.Width, this.Height,
OpenTK.Graphics.PixelFormat.Bgr,
OpenTK.Graphics.PixelType.UnsignedByte,
data.Scan0);
bmp.UnlockBits(data);
bmp.RotateFlip(RotateFlipType.RotateNoneFlipY);
bmp.Save("Screenshot" + (i++).ToString() + ".png", ImageFormat.Png);
}
}
#endregion
#region OnUnload
public override void OnUnload(EventArgs e)
{
if (TextureObject != 0)
GL.DeleteTextures(1, ref TextureObject);
if (ProgramObject != 0)
GL.DeleteProgram(ProgramObject); // implies deleting the previously flagged ShaderObjects
}
#endregion
#region OnResize
/// <summary>
/// Respond to resize events here.
/// </summary>
/// <param name="e">Contains information on the new GameWindow size.</param>
/// <remarks>There is no need to call the base implementation.</remarks>
protected override void OnResize(OpenTK.Platform.ResizeEventArgs e)
{
// Magic numbers so the fractal almost fits inside the window.
// If changing this, also change the -1.6f offset in the fragment shader accordingly.
UniformScaleFactorX = Width / (UniformOffsetX * 2f);
UniformScaleFactorY = Height / (UniformOffsetY * 2f);
GL.Viewport(0, 0, Width, Height);
GL.MatrixMode(MatrixMode.Projection);
GL.LoadIdentity();
GL.Ortho(-1.0, 1.0, -1.0, 1.0, 0.0, 1.0); // 2D setup
GL.MatrixMode(MatrixMode.Modelview);
GL.LoadIdentity();
}
#endregion
#region OnUpdateFrame
/// <summary>
/// Add your game logic here.
/// </summary>
/// <param name="e">Contains timing information.</param>
/// <remarks>There is no need to call the base implementation.</remarks>
public override void OnUpdateFrame(UpdateFrameEventArgs e)
{
base.OnUpdateFrame(e);
if (Keyboard[OpenTK.Input.Key.Escape])
{
this.Exit();
}
}
#endregion
#region OnRenderFrame
/// <summary>
/// Add your game rendering code here.
/// </summary>
/// <param name="e">Contains timing information.</param>
/// <remarks>There is no need to call the base implementation.</remarks>
public override void OnRenderFrame(RenderFrameEventArgs e)
{
//this.Title = "FPS: " + 1 / e.Time;
GL.Clear(ClearBufferMask.ColorBufferBit);
// First, render the next frame of the Julia fractal.
GL.UseProgram(ProgramObject);
// advance the animation by elapsed time, scaling is solely used to make the anim more interesting
AnimOffsetX += (float)(e.Time * AnimSpeedX);
AnimOffsetY += (float)(e.Time * AnimSpeedY);
// pass uniforms into the fragment shader
// first the texture
GL.Uniform1(GL.GetUniformLocation(ProgramObject, "COLORTABLE"), TextureObject);
// the rest are floats
GL.Uniform1(GL.GetUniformLocation(ProgramObject, "CETX"), (float)(Math.Cos(AnimOffsetX) * AnimCosinusPercent));
GL.Uniform1(GL.GetUniformLocation(ProgramObject, "CETY"), (float)(Math.Cos(AnimOffsetY) * AnimCosinusPercent));
GL.Uniform1(GL.GetUniformLocation(ProgramObject, "SCALINGX"), UniformScaleFactorX);
GL.Uniform1(GL.GetUniformLocation(ProgramObject, "SCALINGY"), UniformScaleFactorY);
GL.Uniform1(GL.GetUniformLocation(ProgramObject, "OFFSETX"), UniformOffsetX);
GL.Uniform1(GL.GetUniformLocation(ProgramObject, "OFFSETY"), UniformOffsetY);
// Fullscreen quad. Using immediate mode, since this app is fragment shader limited anyways.
GL.Begin(BeginMode.Quads);
{
GL.Vertex2(-1.0f, -1.0f);
GL.Vertex2(1.0f, -1.0f);
GL.Vertex2(1.0f, 1.0f);
GL.Vertex2(-1.0f, 1.0f);
}
GL.End();
// Then, render the fps:
GL.UseProgram(0);
printer.Begin();
printer.Print((1 / e.Time).ToString("F2"), font, Color.PaleGoldenrod, RectangleF.Empty, TextPrinterOptions.NoCache);
printer.End();
SwapBuffers();
}
#endregion
#region public static void Main()
/// <summary>
/// Entry point of this example.
/// </summary>
[STAThread]
public static void Main()
{
using (JuliaSetFractal example = new JuliaSetFractal())
{
Utilities.SetWindowTitle(example);
example.Run(30.0);
}
}
#endregion
}
}