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Bad Performance of sharpGL inside WPF

I have followed a SharpGL tutorial that can display a rotating block. Initially this only had default colors drawn on it with gl.Color(r, g, b). After this succeeded I tried to texture the cube with an uv map.
When I run the application fullscreen while only coloring the cube (with the sharpGL component covering the entire inside of the application) I get 70~80 fps only for displaying a colored cube. When I enable OpenGL.GL_TEXTURE_2D and draw the textures on a singular cube I get 8~9 fps.
Whenever a bitmap is loaded for use as a texture, it is stored in the memory. This drop in framerates only occurs after I enable OpenGL.GL_TEXTURE_2D and call gl.TexCoord(c1, c2) for all coordinates. Actually moving the object with gl.Rotate(angle, x, y, z) does not noticably affect performance.
The provided data for the method including GetBlockUv and CubeCoordinates are static float-arrays.
Is SharpGL supposed to perform this poorly (i.e. on displaying a singular cube) or is there another reason? Am I doing something wrong that is affecting performance? Is applying textures supposed to affect the performance like that?
The main draw Event happens in a Block:
public void DrawBlock(object sender, OpenGLEventArgs args)
{
// Get the OpenGL instance that's been passed to us.
OpenGL gl = args.OpenGL;
// Reset the modelview.
gl.LoadIdentity();
// Move the block to its location
gl.Translate(Coord.X, Coord.Y, Coord.Z);
gl.Rotate(angle, 1.0f, 1.0f, 0.5f);
angle += 3;
// retrieve the right texture for this block and bind it.
Texture blockTex = BlockTexture.GetBlockTexture(gl, _type);
blockTex.Bind(gl);
// retrieve the uv map for this block
float[] uv = BlockTexture.GetBlockUv(_type);
// retrieve the coordinates for a cube
float[] cube = CubeCoordinates();
gl.Enable(OpenGL.GL_TEXTURE_2D);
// Draw the cube with the bound texture.
gl.Begin(OpenGL.GL_QUADS);
//
//
// Begin by allowing all colors.
gl.Color(1.0f, 1.0f, 1.0f);
// since the uv index increments with 2 each time, we will be keeping track of this separately.
int uvInd = 0;
// i denotes the current coordinate. Each coordinate consists of 3
// values (x, y, z), thus letting us skip 3.
//
// Seeing as we are creating quads, it is expected that cube.Length
// is 3 * 4 * N (where n is a whole number)
for (int i = 0; i < cube.Length; i += 3)
{
// color experiment
//if (i < cube.Length / 3)
//{
// gl.Color(1.0f, 0.00f, 0.00f);
//}
//else if (i < 2 * (cube.Length / 3))
//{
// gl.Color(0.0f, 1.0f, 0.0f);
//}
//else
//{
// gl.Color(0.0f, 0.0f, 1.0f);
//}
try
{
// set the coordinate for the texture
gl.TexCoord(uv[uvInd], uv[uvInd + 1]);
// set the vertex
gl.Vertex(cube[i], cube[i + 1], cube[i + 2]);
}
catch (IndexOutOfRangeException e)
{
throw new IndexOutOfRangeException(
"This exception is thrown because the cube map and uv map do not match size");
}
// increment the uv index
uvInd += 2;
}
gl.End();
gl.Disable(OpenGL.GL_TEXTURE_2D);
}
OpenGL is initialized elsewhere
private void OpenGLControl_OpenGLDraw(object sender, OpenGLEventArgs args)
{
// Get the OpenGL instance that's been passed to us.
OpenGL gl = args.OpenGL;
// Clear the color and depth buffers.
gl.Clear(OpenGL.GL_COLOR_BUFFER_BIT | OpenGL.GL_DEPTH_BUFFER_BIT);
// call the draw method of the GameRunner if the
// GameRunner has already been created.
game?.DrawOpenGL(sender, args);
// Flush OpenGL.
gl.Flush();
}
private void OpenGLControl_OpenGLInitialized(object sender, OpenGLEventArgs args)
{
// Enable the OpenGL depth testing functionality.
args.OpenGL.Enable(OpenGL.GL_DEPTH_TEST);
}
All the intermediate GameRunner does right now is call the DrawBlock routine.
What I mainly would want to know is some insight into the performance I can expect of openGL / sharpGL and whether there are better alternatives. I would like to keep using the WPF architecture surrounding the game, but if openGL inside WPF is more meant as a gimmick, that might not be the best course of action.

I've been having the exact same issue, and it seems to be the case that either SharpGL or the WPF control itself are using software rendering. I tested this by disabling my main display adapter in Device Manager and got the exact same performance as I did with it enabled.
I don't know how to enable hardware acceleration though, so I don't actually know how to fix the issue.

GUIText is behind GUITexture

First off I have looked around and I can see many posts about this and they all point towards the Z position of the text, however I have changed this to minus and positive and my text is always drawn behind my GUITexture.
So this is what I have setup
My GUI has 4 text boxes
Score
Lives
Level
Time
Now I have an object called GameManager which uses this code below to draw my two GUI sprites
void OnGUI()
{
float screenHeight = Screen.height / 12f * 1.5f;
GUI.DrawTexture (new Rect (0, 0, Screen.width * 2, screenHeight), textureBand);
GUI.DrawTexture (new Rect (0, Screen.height - screenHeight, Screen.width * 2, screenHeight), textureBand);
}
However what ever I do my text is always drawn below my GUITexture so I can never see my text, could I get a little help with this one.

If you're drawing into the same location, you need to specify the depth of each draw to make sure they're sorted correctly. Take a look at the unity docs here:
http://docs.unity3d.com/ScriptReference/GUI-depth.html
Set a higher depth value for the textures you want drawn further back (behind the text) like so:
GUI.depth = 1;

Whirl effect with HLSL, starting from Microsoft SpriteEffects sample

The sample
If you watch the code, I'm interested in refraction.fx, and in void DrawRefractGlacier(GameTime gameTime) function. Here you can notice that the function uses a texture to render water distortion on an image (waterfall.jpg as "distorter image", and glacier.jpg as distorted image).
If you read inside refraction.fx, at the beginning it says:
// Effect uses a scrolling displacement texture to offset the position of the main
// texture. Depending on the contents of the displacement texture, this can give a
// wide range of refraction, rippling, warping, and swirling type effects.
It seems that would be easy to achieve another effect by changing the image. I tried that with an image like this:
I want to achieve the effect of distorting everything around as a rotating whirl, or a spiral. How can I do that?
Some simple sequential screen of how it looks with my texture:
Refraction shader:
// Effect uses a scrolling displacement texture to offset the position of the main
// texture. Depending on the contents of the displacement texture, this can give a
// wide range of refraction, rippling, warping, and swirling type effects.
float2 DisplacementScroll;
float2 angle;
sampler TextureSampler : register(s0);
sampler DisplacementSampler : register(s1);
float2x2 RotationMatrix(float rotation)
{
float c = cos(rotation);
float s = sin(rotation);
return float2x2(c, -s, s ,c);
}
float4 main(float4 color : COLOR0, float2 texCoord : TEXCOORD0) : COLOR0
{
float2 rotated_texcoord = texCoord;
rotated_texcoord -= float2(0.25, 0.25);
rotated_texcoord = mul(rotated_texcoord, RotationMatrix(angle));
rotated_texcoord += float2(0.25, 0.25);
float2 DispScroll = DisplacementScroll;
// Look up the displacement amount.
float2 displacement = tex2D(DisplacementSampler, DispScroll+ texCoord / 3);
// Offset the main texture coordinates.
texCoord += displacement * 0.2 - 0.15;
// Look up into the main texture.
return tex2D(TextureSampler, texCoord) * color;
}
technique Refraction
{
pass Pass1
{
PixelShader = compile ps_2_0 main();
}
}
Its draw call:
void DrawRefractGlacier(GameTime gameTime)
{
// Set an effect parameter to make the
// displacement texture scroll in a giant circle.
refractionEffect.Parameters["DisplacementScroll"].SetValue(
MoveInCircle(gameTime, 0.2f));
// Set the displacement texture.
graphics.GraphicsDevice.Textures[1] = waterfallTexture;
// Begin the sprite batch.
spriteBatch.Begin(0, null, null, null, null, refractionEffect);
// Because the effect will displace the texture coordinates before
// sampling the main texture, the coordinates could sometimes go right
// off the edges of the texture, which looks ugly. To prevent this, we
// adjust our sprite source region to leave a little border around the
// edge of the texture. The displacement effect will then just move the
// texture coordinates into this border region, without ever hitting
// the edge of the texture.
Rectangle croppedGlacier = new Rectangle(32, 32,
glacierTexture.Width - 64,
glacierTexture.Height - 64);
spriteBatch.Draw(glacierTexture,
GraphicsDevice.Viewport.Bounds,
croppedGlacier,
Color.White);
// End the sprite batch.
spriteBatch.End();
}

Drawn quads, lines, points in opentk don't show up right

I've got drawing sprites to work with OpenTK in my 2d game engine now. Only problem I'm having is that custom drawn objects with opengl (anything but sprites really) show up as the background color. Example:
I'm Drawing a 2.4f width black line here. There's also a quad and a point in the example, but they do not overlap anything that's actually visible. The line overlaps the magenta sprite, but the color is just wrong. My question is: Am I missing an OpenGL feature, or doing something horrible wrong?
These are the samples of my project concerning drawing: (you can also find the project on https://github.com/Villermen/HatlessEngine if there's questions about the code)
Initialization:
Window = new GameWindow(windowSize.Width, windowSize.Height);
//OpenGL initialization
GL.Enable(EnableCap.PointSmooth);
GL.Hint(HintTarget.PointSmoothHint, HintMode.Nicest);
GL.Enable(EnableCap.LineSmooth);
GL.Hint(HintTarget.LineSmoothHint, HintMode.Nicest);
GL.Enable(EnableCap.Blend);
GL.BlendFunc(BlendingFactorSrc.SrcAlpha, BlendingFactorDest.OneMinusSrcAlpha);
GL.ClearColor(Color.Gray);
GL.Enable(EnableCap.Texture2D);
GL.Enable(EnableCap.DepthTest);
GL.DepthFunc(DepthFunction.Lequal);
GL.ClearDepth(1d);
GL.DepthRange(1d, 0d); //does not seem right, but it works (see it as duct-tape)
Every draw cycle:
GL.Clear(ClearBufferMask.ColorBufferBit | ClearBufferMask.DepthBufferBit);
//reset depth and color to be consistent over multiple frames
DrawX.Depth = 0;
DrawX.DefaultColor = Color.Black;
foreach(View view in Resources.Views)
{
CurrentDrawArea = view.Area;
GL.Viewport((int)view.Viewport.Left * Window.Width, (int)view.Viewport.Top * Window.Height, (int)view.Viewport.Right * Window.Width, (int)view.Viewport.Bottom * Window.Height);
GL.MatrixMode(MatrixMode.Projection);
GL.LoadIdentity();
GL.Ortho(view.Area.Left, view.Area.Right, view.Area.Bottom, view.Area.Top, -1f, 1f);
GL.MatrixMode(MatrixMode.Modelview);
//drawing
foreach (LogicalObject obj in Resources.Objects)
{
//set view's coords for clipping?
obj.Draw();
}
}
GL.Flush();
Window.Context.SwapBuffers();
DrawX.Line:
public static void Line(PointF pos1, PointF pos2, Color color, float width = 1)
{
RectangleF lineRectangle = new RectangleF(pos1.X, pos1.Y, pos2.X - pos1.X, pos2.Y - pos1.Y);
if (lineRectangle.IntersectsWith(Game.CurrentDrawArea))
{
GL.LineWidth(width);
GL.Color3(color);
GL.Begin(PrimitiveType.Lines);
GL.Vertex3(pos1.X, pos1.Y, GLDepth);
GL.Vertex3(pos2.X, pos2.Y, GLDepth);
GL.End();
}
}
Edit: If I disable the blendcap before and enable it after drawing the line it does show up with the right color, but I must have it blended.

I forgot to unbind the texture in the texture-drawing method...
GL.BindTexture(TextureTarget.Texture2D, 0);

Positioning Graphics draw

I'm trying to draw some polygons and lines usinng e.Graphics.DrawPolygon (or DrawLine). But I have a little problem specifying the coordinates where to draw. I am drawing onto a PictureBox using its Paint event. The elements draw correctly relatively to each other (creating the required final picture), but seem always to draw in the upper-left corner of the PictureBox. When creating the points to draw, when I just try to multiply the coordinates, it draws it at the same place but bigger (size is multiplied, instead of location coordinates).
Here is my code:
//some for loop
{
//getting the coordinates
Point toAdd = new Point((int)xCoord, (int)yCoord); // creating the point from originaly a double, here i tried to multiply..
tmpPoints.Add(toAdd); // tmpPoints is a List<Point>
}
points.Add(tmpPoints.ToArray()); //List<Point[]>
drawBuffer = points; //saving to a public List<Point[]>
points.Clear();
this.Invalidate();
here part of the pictureBox1_Paint method:
for (int i = 0; i < drawBuffer.Count; i++)
{
//some other stuff like deciding which color to use, not very important
Brush br = new SolidBrush(polyColor);
e.Graphics.FillPolygon(br, drawBuffer[i]);
brush.Dispose();
}
I have checked using breakpoint, the coordiinates are the same ratio (what was 100 pixels wide is still 100 pixels wide), they are at coordinates like x 3000 and y 1500, but it just draws itself in the upper-left corner. When i multiply the coordinates 3 times (see the code for the place where i multiplied), it draws at the same place but 3 times bigger (doesn't make sense after checking the coords...)
So, my question is - how do I set the location correctly, or is there any other way to do this?
Like this (I know, this is nonsense, just an example)
foreach(Polygon poly in e.Graphics)
{
poly.Location = new Point(poly.Location.X * 2, poly.Location.Y * 2);
}

When you multiply the coordinates of the points, they're scaled around the point (0, 0), the top-left corner of the canvas:
In order to scale it around its center (and I suppose you expected it to work this way), you need to calculate some kind of center of the polygon. For simplicity, it can be even an arithmetic mean of the coordinates, on X and Y axes respectively. If you already have the coordinates of the center, translate the coordinates of every point by a reversed vector made from the center coordinates (this is how it would look like if you drew it after this operation - the polygon's center is in the center of the coordinate system):
Now, do your scaling:
and move it back by the vector of polygon's center coordinates:

when you multiply
poly.Location = new Point(poly.Location.X * 2, poly.Location.Y * 2);
you are doing a stretch operation when you add
poly.Location = new Point(poly.Location.X + 50, poly.Location.Y +50); you are doing a translation operation.

If you want to shift everything without modifying the stored coords then just translate the graphics before drawing:
private void pictureBox1_Paint(object sender, PaintEventArgs e)
{
e.Graphics.TranslateTransform(100, 100); // shift the origin somehow
// ... draw the polygons as before ...
}