osu/osu.Game/Graphics/Backgrounds/TrianglesV2.cs

323 lines
12 KiB
C#

// Copyright (c) ppy Pty Ltd <contact@ppy.sh>. Licensed under the MIT Licence.
// See the LICENCE file in the repository root for full licence text.
using osu.Framework.Utils;
using osuTK;
using System;
using osu.Framework.Graphics.Shaders;
using osu.Framework.Graphics.Textures;
using osu.Framework.Graphics.Primitives;
using osu.Framework.Allocation;
using System.Collections.Generic;
using osu.Framework.Graphics.Rendering;
using osu.Framework.Graphics.Rendering.Vertices;
using osu.Framework.Graphics.Colour;
using osu.Framework.Bindables;
using osu.Framework.Graphics;
namespace osu.Game.Graphics.Backgrounds
{
public partial class TrianglesV2 : Drawable
{
private const float triangle_size = 100;
private const float base_velocity = 50;
/// <summary>
/// sqrt(3) / 2
/// </summary>
private const float equilateral_triangle_ratio = 0.866f;
public float Thickness { get; set; } = 0.02f; // No need for invalidation since it's happening in Update()
/// <summary>
/// Whether we should create new triangles as others expire.
/// </summary>
protected virtual bool CreateNewTriangles => true;
/// <summary>
/// If enabled, only the portion of triangles that falls within this <see cref="Drawable"/>'s
/// shape is drawn to the screen.
/// </summary>
public bool Masking { get; set; }
private readonly BindableFloat spawnRatio = new BindableFloat(1f);
/// <summary>
/// The amount of triangles we want compared to the default distribution.
/// </summary>
public float SpawnRatio
{
get => spawnRatio.Value;
set => spawnRatio.Value = value;
}
/// <summary>
/// The relative velocity of the triangles. Default is 1.
/// </summary>
public float Velocity = 1;
private readonly List<TriangleParticle> parts = new List<TriangleParticle>();
private Random? stableRandom;
private IShader shader = null!;
private Texture texture = null!;
/// <summary>
/// Construct a new triangle visualisation.
/// </summary>
/// <param name="seed">An optional seed to stabilise random positions / attributes. Note that this does not guarantee stable playback when seeking in time.</param>
public TrianglesV2(int? seed = null)
{
if (seed != null)
stableRandom = new Random(seed.Value);
}
[BackgroundDependencyLoader]
private void load(ShaderManager shaders, IRenderer renderer)
{
shader = shaders.Load(VertexShaderDescriptor.TEXTURE_2, "TriangleBorder");
texture = renderer.WhitePixel;
}
protected override void LoadComplete()
{
base.LoadComplete();
spawnRatio.BindValueChanged(_ => Reset(), true);
}
protected override void Update()
{
base.Update();
Invalidate(Invalidation.DrawNode);
if (CreateNewTriangles)
addTriangles(false);
float elapsedSeconds = (float)Time.Elapsed / 1000;
// Since position is relative, the velocity needs to scale inversely with DrawHeight.
float movedDistance = -elapsedSeconds * Velocity * base_velocity / DrawHeight;
for (int i = 0; i < parts.Count; i++)
{
TriangleParticle newParticle = parts[i];
newParticle.Position.Y += Math.Max(0.5f, parts[i].SpeedMultiplier) * movedDistance;
parts[i] = newParticle;
float bottomPos = parts[i].Position.Y + triangle_size * equilateral_triangle_ratio / DrawHeight;
if (bottomPos < 0)
parts.RemoveAt(i);
}
}
/// <summary>
/// Clears and re-initialises triangles according to a given seed.
/// </summary>
/// <param name="seed">An optional seed to stabilise random positions / attributes. Note that this does not guarantee stable playback when seeking in time.</param>
public void Reset(int? seed = null)
{
if (seed != null)
stableRandom = new Random(seed.Value);
parts.Clear();
addTriangles(true);
}
protected int AimCount { get; private set; }
private void addTriangles(bool randomY)
{
// Limited by the maximum size of QuadVertexBuffer for safety.
const int max_triangles = ushort.MaxValue / (IRenderer.VERTICES_PER_QUAD + 2);
AimCount = (int)Math.Clamp(DrawWidth * 0.02f * SpawnRatio, 1, max_triangles);
int currentCount = parts.Count;
for (int i = 0; i < AimCount - currentCount; i++)
parts.Add(createTriangle(randomY));
}
private TriangleParticle createTriangle(bool randomY)
{
TriangleParticle particle = CreateTriangle();
float y = 1;
if (randomY)
{
// since triangles are drawn from the top - allow them to be positioned a bit above the screen
float maxOffset = triangle_size * equilateral_triangle_ratio / DrawHeight;
y = Interpolation.ValueAt(nextRandom(), -maxOffset, 1f, 0f, 1f);
}
particle.Position = new Vector2(nextRandom(), y);
return particle;
}
/// <summary>
/// Creates a triangle particle with a random speed multiplier.
/// </summary>
/// <returns>The triangle particle.</returns>
protected virtual TriangleParticle CreateTriangle()
{
const float std_dev = 0.16f;
const float mean = 0.5f;
float u1 = 1 - nextRandom(); //uniform(0,1] random floats
float u2 = 1 - nextRandom();
float randStdNormal = (float)(Math.Sqrt(-2.0 * Math.Log(u1)) * Math.Sin(2.0 * Math.PI * u2)); // random normal(0,1)
float speedMultiplier = Math.Max(mean + std_dev * randStdNormal, 0.1f); // random normal(mean,stdDev^2)
return new TriangleParticle { SpeedMultiplier = speedMultiplier };
}
private float nextRandom() => (float)(stableRandom?.NextDouble() ?? RNG.NextSingle());
protected override DrawNode CreateDrawNode() => new TrianglesDrawNode(this);
private class TrianglesDrawNode : DrawNode
{
protected new TrianglesV2 Source => (TrianglesV2)base.Source;
private IShader shader = null!;
private Texture texture = null!;
private readonly List<TriangleParticle> parts = new List<TriangleParticle>();
private readonly Vector2 triangleSize = new Vector2(1f, equilateral_triangle_ratio) * triangle_size;
private Vector2 size;
private float thickness;
private float texelSize;
private bool masking;
private IVertexBatch<TexturedVertex2D>? vertexBatch;
public TrianglesDrawNode(TrianglesV2 source)
: base(source)
{
}
public override void ApplyState()
{
base.ApplyState();
shader = Source.shader;
texture = Source.texture;
size = Source.DrawSize;
thickness = Source.Thickness;
masking = Source.Masking;
Quad triangleQuad = new Quad(
Vector2Extensions.Transform(Vector2.Zero, DrawInfo.Matrix),
Vector2Extensions.Transform(new Vector2(triangle_size, 0f), DrawInfo.Matrix),
Vector2Extensions.Transform(new Vector2(0f, triangleSize.Y), DrawInfo.Matrix),
Vector2Extensions.Transform(triangleSize, DrawInfo.Matrix)
);
texelSize = 1.5f / triangleQuad.Height;
parts.Clear();
parts.AddRange(Source.parts);
}
public override void Draw(IRenderer renderer)
{
base.Draw(renderer);
if (Source.AimCount == 0 || thickness == 0)
return;
if (vertexBatch == null || vertexBatch.Size != Source.AimCount)
{
vertexBatch?.Dispose();
vertexBatch = renderer.CreateQuadBatch<TexturedVertex2D>(Source.AimCount, 1);
}
shader.Bind();
shader.GetUniform<float>("thickness").UpdateValue(ref thickness);
shader.GetUniform<float>("texelSize").UpdateValue(ref texelSize);
Vector2 relativeSize = Vector2.Divide(triangleSize, size);
foreach (TriangleParticle particle in parts)
{
Vector2 topLeft = particle.Position - new Vector2(relativeSize.X * 0.5f, 0f);
Quad triangleQuad = masking ? clampToDrawable(topLeft, relativeSize) : new Quad(topLeft.X, topLeft.Y, relativeSize.X, relativeSize.Y);
var drawQuad = new Quad(
Vector2Extensions.Transform(triangleQuad.TopLeft * size, DrawInfo.Matrix),
Vector2Extensions.Transform(triangleQuad.TopRight * size, DrawInfo.Matrix),
Vector2Extensions.Transform(triangleQuad.BottomLeft * size, DrawInfo.Matrix),
Vector2Extensions.Transform(triangleQuad.BottomRight * size, DrawInfo.Matrix)
);
ColourInfo colourInfo = triangleColourInfo(DrawColourInfo.Colour, triangleQuad);
RectangleF textureCoords = new RectangleF(
triangleQuad.TopLeft.X - topLeft.X,
triangleQuad.TopLeft.Y - topLeft.Y,
triangleQuad.Width,
triangleQuad.Height
) / relativeSize;
renderer.DrawQuad(texture, drawQuad, colourInfo, new RectangleF(0, 0, 1, 1), vertexBatch.AddAction, textureCoords: textureCoords);
}
shader.Unbind();
}
private static ColourInfo triangleColourInfo(ColourInfo source, Quad quad)
{
return new ColourInfo
{
TopLeft = source.Interpolate(quad.TopLeft),
TopRight = source.Interpolate(quad.TopRight),
BottomLeft = source.Interpolate(quad.BottomLeft),
BottomRight = source.Interpolate(quad.BottomRight)
};
}
private static Quad clampToDrawable(Vector2 topLeft, Vector2 size)
{
float leftClamped = Math.Clamp(topLeft.X, 0f, 1f);
float topClamped = Math.Clamp(topLeft.Y, 0f, 1f);
return new Quad(
leftClamped,
topClamped,
Math.Clamp(topLeft.X + size.X, 0f, 1f) - leftClamped,
Math.Clamp(topLeft.Y + size.Y, 0f, 1f) - topClamped
);
}
protected override void Dispose(bool isDisposing)
{
base.Dispose(isDisposing);
vertexBatch?.Dispose();
}
}
protected struct TriangleParticle
{
/// <summary>
/// The position of the top vertex of the triangle.
/// </summary>
public Vector2 Position;
/// <summary>
/// The speed multiplier of the triangle.
/// </summary>
public float SpeedMultiplier;
}
}
}