public static void CreateVAO(this StaticBackground background, VertexLayout vertexLayout, BaseRenderer renderer)
{
try
{
float y0, y1;
if (background.KeepAspectRatio)
{
int tw = background.Texture.Width;
int th = background.Texture.Height;
double hh = System.Math.PI * background.BackgroundImageDistance * th / (tw * background.Repetition);
y0 = (float)(-0.5 * hh);
y1 = (float)(1.5 * hh);
}
else
{
y0 = (float)(-0.125 * background.BackgroundImageDistance);
y1 = (float)(0.375 * background.BackgroundImageDistance);
}
const int n = 32;
Vector3f[] bottom = new Vector3f[n];
Vector3f[] top = new Vector3f[n];
double angleValue = 2.61799387799149 - 3.14159265358979 / n;
const double angleIncrement = 6.28318530717958 / n;
/*
* To ensure that the whole background cylinder is rendered inside the viewing frustum,
* the background is rendered before the scene with z-buffer writes disabled. Then,
* the actual distance from the camera is irrelevant as long as it is inside the frustum.
* */
for (int i = 0; i < n; i++)
{
float x = (float)(background.BackgroundImageDistance * System.Math.Cos(angleValue));
float z = (float)(background.BackgroundImageDistance * System.Math.Sin(angleValue));
bottom[i] = new Vector3f(x, y0, z);
top[i] = new Vector3f(x, y1, z);
angleValue += angleIncrement;
}
float textureStart = 0.5f * (float)background.Repetition / n;
float textureIncrement = -(float)background.Repetition / n;
float textureX = textureStart;
List <LibRenderVertex> vertexData = new List <LibRenderVertex>();
List <ushort> indexData = new List <ushort>();
for (int i = 0; i < n; i++)
{
int j = (i + 1) % n;
int indexOffset = vertexData.Count;
// side wall
vertexData.Add(new LibRenderVertex
{
Position = top[i],
UV = new Vector2f(textureX, 0.005f),
Color = Color128.White
});
vertexData.Add(new LibRenderVertex
{
Position = bottom[i],
UV = new Vector2f(textureX, 0.995f),
Color = Color128.White
});
vertexData.Add(new LibRenderVertex
{
Position = bottom[j],
UV = new Vector2f(textureX + textureIncrement, 0.995f),
Color = Color128.White
});
vertexData.Add(new LibRenderVertex
{
Position = top[j],
UV = new Vector2f(textureX + textureIncrement, 0.005f),
Color = Color128.White
});
indexData.AddRange(new[] { 0, 1, 2, 3 }.Select(x => x + indexOffset).Select(x => (ushort)x));
// top cap
vertexData.Add(new LibRenderVertex
{
Position = new Vector3f(0.0f, top[i].Y, 0.0f),
UV = new Vector2f(textureX + 0.5f * textureIncrement, 0.1f),
Color = Color128.White
});
indexData.AddRange(new[] { 0, 3, 4 }.Select(x => x + indexOffset).Select(x => (ushort)x));
// bottom cap
vertexData.Add(new LibRenderVertex
{
Position = new Vector3f(0.0f, bottom[i].Y, 0.0f),
UV = new Vector2f(textureX + 0.5f * textureIncrement, 0.9f),
Color = Color128.White
});
indexData.AddRange(new[] { 5, 2, 1 }.Select(x => x + indexOffset).Select(x => (ushort)x));
// finish
textureX += textureIncrement;
}
VertexArrayObject VAO = (VertexArrayObject)background.VAO;
VAO?.UnBind();
VAO?.Dispose();
VAO = new VertexArrayObject();
VAO.Bind();
VAO.SetVBO(new VertexBufferObject(vertexData.ToArray(), BufferUsageHint.StaticDraw));
VAO.SetIBO(new IndexBufferObjectU(indexData.ToArray(), BufferUsageHint.StaticDraw));
VAO.SetAttributes(vertexLayout);
VAO.UnBind();
background.VAO = VAO;
}
catch (Exception e)
{
renderer.ForceLegacyOpenGL = true;
renderer.currentHost.AddMessage(MessageType.Error, false, "Creating VAO failed with the following error: " + e);
}
}
/// <summary>Create an OpenGL/OpenTK VAO for a mesh</summary>
/// <param name="isDynamic"></param>
public static void CreateVAO(ref Mesh mesh, bool isDynamic, VertexLayout vertexLayout, BaseRenderer renderer)
{
try
{
var hint = isDynamic ? BufferUsageHint.DynamicDraw : BufferUsageHint.StaticDraw;
var vertexData = new List <LibRenderVertex>();
var indexData = new List <uint>();
var normalsVertexData = new List <LibRenderVertex>();
var normalsIndexData = new List <uint>();
for (int i = 0; i < mesh.Faces.Length; i++)
{
mesh.Faces[i].IboStartIndex = indexData.Count;
mesh.Faces[i].NormalsIboStartIndex = normalsIndexData.Count;
foreach (var vertex in mesh.Faces[i].Vertices)
{
var data = new LibRenderVertex
{
Position = mesh.Vertices[vertex.Index].Coordinates,
Normal = vertex.Normal,
UV = new Vector2f(mesh.Vertices[vertex.Index].TextureCoordinates)
};
var coloredVertex = mesh.Vertices[vertex.Index] as ColoredVertex;
if (coloredVertex != null)
{
data.Color = coloredVertex.Color;
}
else
{
data.Color = Color128.Transparent;
}
vertexData.Add(data);
var normalsData = new LibRenderVertex[2];
normalsData[0].Position = data.Position;
normalsData[1].Position = data.Position + data.Normal;
for (int j = 0; j < normalsData.Length; j++)
{
normalsData[j].Color = Color128.White;
}
normalsVertexData.AddRange(normalsData);
}
indexData.AddRange(Enumerable.Range(mesh.Faces[i].IboStartIndex, mesh.Faces[i].Vertices.Length).Select(x => (uint)x));
normalsIndexData.AddRange(Enumerable.Range(mesh.Faces[i].NormalsIboStartIndex, mesh.Faces[i].Vertices.Length * 2).Select(x => (uint)x));
}
VertexArrayObject VAO = (VertexArrayObject)mesh.VAO;
VAO?.UnBind();
VAO?.Dispose();
VAO = new VertexArrayObject();
VAO.Bind();
VAO.SetVBO(new VertexBufferObject(vertexData.ToArray(), hint));
if (indexData.Count > 65530)
{
//Marginal headroom, although it probably doesn't matter
VAO.SetIBO(new IndexBufferObjectI(indexData.ToArray(), hint));
}
else
{
VAO.SetIBO(new IndexBufferObjectU(indexData.Select(x => (ushort)x).ToArray(), hint));
}
VAO.SetAttributes(vertexLayout);
VAO.UnBind();
mesh.VAO = VAO;
VertexArrayObject NormalsVAO = (VertexArrayObject)mesh.NormalsVAO;
NormalsVAO?.UnBind();
NormalsVAO?.Dispose();
NormalsVAO = new VertexArrayObject();
NormalsVAO.Bind();
NormalsVAO.SetVBO(new VertexBufferObject(normalsVertexData.ToArray(), hint));
if (normalsIndexData.Count > 65530)
{
//Marginal headroom, although it probably doesn't matter
NormalsVAO.SetIBO(new IndexBufferObjectI(normalsIndexData.ToArray(), hint));
}
else
{
NormalsVAO.SetIBO(new IndexBufferObjectU(normalsIndexData.Select(x => (ushort)x).ToArray(), hint));
}
NormalsVAO.SetAttributes(vertexLayout);
NormalsVAO.UnBind();
mesh.NormalsVAO = NormalsVAO;
}
catch (Exception e)
{
renderer.ForceLegacyOpenGL = true;
renderer.currentHost.AddMessage(MessageType.Error, false, "Creating VAO failed with the following error: " + e);
}
}