I have used gl.glines so far. But is there another way or a better way to draw lines more efficiently? (1000 - 2000 lines)
Can i draw lines static with GL?
Thanks in advance:)
I highly reccomend Vectrosity, an amazing $30 plug-in which has the best documentation and ease-of-use of almost any software I’ve ever used.
The website is here:
Starscene Software - Unity Utilities - Vectrosity
I have an app running on Oculus Rift with about 10,000 concurrent animated line segments. Using Vectrosity, it clocks in at about 40fps on a 2012 MacBook Air with no GPU. All those smooth curves you see below are actually long arrays of about 50+ line segments each.
There’s also a more complex version, I found it on the Unity wiki a while ago, works very well.
using System.Reflection;
using UnityEngine;
// Line drawing routine originally courtesy of Linusmartensson:
// http://forum.unity3d.com/threads/71979-Drawing-lines-in-the-editor
//
// Rewritten to improve performance by Yossarian King / August 2013.
//
// This version produces virtually identical results to the original (tested by drawing
// one over the other and observing errors of one pixel or less), but for large numbers
// of lines this version is more than four times faster than the original, and comes
// within about 70% of the raw performance of Graphics.DrawTexture.
//
// Peak performance on my laptop is around 200,000 lines per second. The laptop is
// Windows 7 64-bit, Intel Core2 Duo CPU 2.53GHz, 4G RAM, NVIDIA GeForce GT 220M.
// Line width and anti-aliasing had negligible impact on performance.
//
// For a graph of benchmark results in a standalone Windows build, see this image:
// https://app.box.com/s/hyuhi565dtolqdm97e00
//
// For a Google spreadsheet with full benchmark results, see:
// https://docs.google.com/spreadsheet/ccc?key=0AvJlJlbRO26VdHhzeHNRMVF2UHZHMXFCTVFZN011V1E&usp=sharing
public static class Drawing
{
private static Texture2D aaLineTex = null;
private static Texture2D lineTex = null;
private static Material blitMaterial = null;
private static Material blendMaterial = null;
private static Rect lineRect = new Rect(0, 0, 1, 1);
// Draw a line in screen space, suitable for use from OnGUI calls from either
// MonoBehaviour or EditorWindow. Note that this should only be called during repaint
// events, when (Event.current.type == EventType.Repaint).
//
// Works by computing a matrix that transforms a unit square -- Rect(0,0,1,1) -- into
// a scaled, rotated, and offset rectangle that corresponds to the line and its width.
// A DrawTexture call used to draw a line texture into the transformed rectangle.
//
// More specifically:
// scale x by line length, y by line width
// rotate around z by the angle of the line
// offset by the position of the upper left corner of the target rectangle
//
// By working out the matrices and applying some trigonometry, the matrix calculation comes
// out pretty simple. See https://app.box.com/s/xi08ow8o8ujymazg100j for a picture of my
// notebook with the calculations.
public static void DrawLine(Vector2 pointA, Vector2 pointB, Color color, float width, bool antiAlias)
{
// Normally the static initializer does this, but to handle texture reinitialization
// after editor play mode stops we need this check in the Editor.
#if UNITY_EDITOR
if (!lineTex)
{
Initialize();
}
#endif
// Note that theta = atan2(dy, dx) is the angle we want to rotate by, but instead
// of calculating the angle we just use the sine (dy/len) and cosine (dx/len).
float dx = pointB.x - pointA.x;
float dy = pointB.y - pointA.y;
float len = Mathf.Sqrt(dx * dx + dy * dy);
// Early out on tiny lines to avoid divide by zero.
// Plus what's the point of drawing a line 1/1000th of a pixel long??
if (len < 0.001f)
{
return;
}
// Pick texture and material (and tweak width) based on anti-alias setting.
Texture2D tex;
Material mat;
if (antiAlias)
{
// Multiplying by three is fine for anti-aliasing width-1 lines, but make a wide "fringe"
// for thicker lines, which may or may not be desirable.
width = width * 3.0f;
tex = aaLineTex;
mat = blendMaterial;
}
else
{
tex = lineTex;
mat = blitMaterial;
}
float wdx = width * dy / len;
float wdy = width * dx / len;
Matrix4x4 matrix = Matrix4x4.identity;
matrix.m00 = dx;
matrix.m01 = -wdx;
matrix.m03 = pointA.x + 0.5f * wdx;
matrix.m10 = dy;
matrix.m11 = wdy;
matrix.m13 = pointA.y - 0.5f * wdy;
// Use GL matrix and Graphics.DrawTexture rather than GUI.matrix and GUI.DrawTexture,
// for better performance. (Setting GUI.matrix is slow, and GUI.DrawTexture is just a
// wrapper on Graphics.DrawTexture.)
GL.PushMatrix();
GL.MultMatrix(matrix);
Graphics.DrawTexture(lineRect, tex, lineRect, 0, 0, 0, 0, color, mat);
GL.PopMatrix();
}
// Other than method name, DrawBezierLine is unchanged from Linusmartensson's original implementation.
public static void DrawBezierLine(Vector2 start, Vector2 startTangent, Vector2 end, Vector2 endTangent, Color color, float width, bool antiAlias, int segments)
{
Vector2 lastV = CubeBezier(start, startTangent, end, endTangent, 0);
for (int i = 1; i < segments; ++i)
{
Vector2 v = CubeBezier(start, startTangent, end, endTangent, i/(float)segments);
Drawing.DrawLine(lastV, v, color, width, antiAlias);
lastV = v;
}
}
private static Vector2 CubeBezier(Vector2 s, Vector2 st, Vector2 e, Vector2 et, float t)
{
float rt = 1 - t;
return rt * rt * rt * s + 3 * rt * rt * t * st + 3 * rt * t * t * et + t * t * t * e;
}
// This static initializer works for runtime, but apparently isn't called when
// Editor play mode stops, so DrawLine will re-initialize if needed.
static Drawing()
{
Initialize();
}
private static void Initialize()
{
if (lineTex == null)
{
lineTex = new Texture2D(1, 1, TextureFormat.ARGB32, false);
lineTex.SetPixel(0, 1, Color.white);
lineTex.Apply();
}
if (aaLineTex == null)
{
// TODO: better anti-aliasing of wide lines with a larger texture? or use Graphics.DrawTexture with border settings
aaLineTex = new Texture2D(1, 3, TextureFormat.ARGB32, false);
aaLineTex.SetPixel(0, 0, new Color(1, 1, 1, 0));
aaLineTex.SetPixel(0, 1, Color.white);
aaLineTex.SetPixel(0, 2, new Color(1, 1, 1, 0));
aaLineTex.Apply();
}
// GUI.blitMaterial and GUI.blendMaterial are used internally by GUI.DrawTexture,
// depending on the alphaBlend parameter. Use reflection to "borrow" these references.
blitMaterial = (Material)typeof(GUI).GetMethod("get_blitMaterial", BindingFlags.NonPublic | BindingFlags.Static).Invoke(null, null);
blendMaterial = (Material)typeof(GUI).GetMethod("get_blendMaterial", BindingFlags.NonPublic | BindingFlags.Static).Invoke(null, null);
}
}