GeezerVison is showing github.com — libprocessing/examples/particles_lifecycle.rs at python-api · processing/libprocessing

Expand file tree

particles_lifecycle.rs

Copy path

More file actions

Latest commit

History

175 lines (153 loc) · 5.41 KB

particles_lifecycle.rs

Copy path

File metadata and controls

175 lines (153 loc) · 5.41 KB

Raw

Copy raw file

Download raw file

Open symbols panel

Edit and raw actions

100

101

102

103

104

105

106

107

108

109

110

111

112

113

114

115

116

117

118

119

120

121

122

123

124

125

126

127

128

129

130

131

132

133

134

135

136

137

138

139

140

141

142

143

144

145

146

147

148

149

150

151

152

153

154

155

156

157

158

159

160

161

162

163

164

165

166

167

168

169

170

171

172

173

174

175

use processing_glfw::GlfwContext;

use bevy::math::Vec3;

use processing::prelude::*;

use processing_render::geometry::AttributeFormat;

use processing_render::render::command::DrawCommand;

const AGING_SHADER: &str = r#"

@group(0) @binding(0) var<storage, read_write> age: array<f32>;

@group(0) @binding(1) var<storage, read_write> life: array<f32>;

@group(0) @binding(2) var<storage, read_write> position: array<f32>;

@group(0) @binding(3) var<storage, read_write> scale: array<f32>;

@group(0) @binding(4) var<uniform> params: vec4<f32>; // x = dt, y = ttl

@compute @workgroup_size(64)

fn main(@builtin(global_invocation_id) gid: vec3<u32>) {

let i = gid.x;

let count = arrayLength(&age);

if i >= count {

return;

}

let dt = params.x;

let ttl = params.y;

if life[i] <= 0.0 {

return;

}

age[i] = age[i] + dt;

position[i * 3u + 1u] = position[i * 3u + 1u] - dt * 1.5;

let remaining = clamp(1.0 - age[i] / ttl, 0.0, 1.0);

let s = remaining * remaining;

scale[i * 3u + 0u] = s;

scale[i * 3u + 1u] = s;

scale[i * 3u + 2u] = s;

if age[i] > ttl {

life[i] = 0.0;

}

"#;

fn main() {

sketch().unwrap();

exit(0).unwrap();

}

fn sketch() -> error::Result<()> {

let mut glfw_ctx = GlfwContext::new(900, 700, false)?;

init(Config::default())?;

let surface = glfw_ctx.create_surface(900, 700, false)?;

let graphics = graphics_create(surface, 900, 700, TextureFormat::Rgba16Float)?;

graphics_mode_3d(graphics)?;

transform_set_position(graphics, Vec3::new(0.0, 2.0, 14.0))?;

transform_look_at(graphics, Vec3::new(0.0, 0.0, 0.0))?;

let sphere = geometry_sphere(0.1, 8, 6)?;

let capacity: u32 = 800;

let position_attr = geometry_attribute_position();

let color_attr = geometry_attribute_color();

let scale_attr = geometry_attribute_scale();

let life_attr = geometry_attribute_life();

let age_attr = geometry_attribute_create("age", AttributeFormat::Float)?;

let p = particles_create(

capacity,

vec![position_attr, color_attr, scale_attr, life_attr, age_attr],

)?;

let color_buf =

particles_buffer(p, color_attr)?.ok_or(error::ProcessingError::ParticlesNotFound)?;

let mat = {

let m = material_create_unlit()?;

material_set_albedo_buffer(m, color_buf)?;

};

let aging_shader = shader_create(AGING_SHADER)?;

let aging = compute_create(aging_shader)?;

let burst: u32 = 6;

let dt: f32 = 1.0 / 60.0;

let ttl: f32 = 1.0;

let mut frame: u32 = 0;

while glfw_ctx.poll_events() {

graphics_begin_draw(graphics)?;

graphics_record_command(

graphics,

DrawCommand::BackgroundColor(bevy::color::Color::srgb(0.04, 0.04, 0.07)),

)?;

graphics_record_command(graphics, DrawCommand::Material(mat))?;

graphics_record_command(

graphics,

DrawCommand::Particles {

particles: p,

geometry: Some(sphere),

topology: Default::default(),

)?;

graphics_end_draw(graphics)?;

let mut positions: Vec<f32> = Vec::with_capacity(burst as usize * 3);

let mut colors: Vec<f32> = Vec::with_capacity(burst as usize * 4);

for k in 0..burst {

let i = frame * burst + k;

let u = ((i.wrapping_mul(2654435761) >> 8) & 0xFFFF) as f32 / 65535.0;

let v = ((i.wrapping_mul(40503) >> 8) & 0xFFFF) as f32 / 65535.0;

let theta = u * std::f32::consts::TAU;

let r = v * 0.6;

positions.push(theta.cos() * r);

positions.push(2.5);

positions.push(theta.sin() * r);

let h = (i as f32 * 0.013) % 1.0;

let (cr, cg, cb) = hsv_to_rgb(h, 0.85, 1.0);

colors.push(cr);

colors.push(cg);

colors.push(cb);

colors.push(1.0);

}

let position_bytes: Vec<u8> = positions.iter().flat_map(|f| f.to_le_bytes()).collect();

let color_bytes: Vec<u8> = colors.iter().flat_map(|f| f.to_le_bytes()).collect();

let zero_floats: Vec<u8> = (0..burst).flat_map(|_| 0.0_f32.to_le_bytes()).collect();

let one_floats: Vec<u8> = (0..burst).flat_map(|_| 1.0_f32.to_le_bytes()).collect();

let one_scale: Vec<u8> = (0..burst)

.flat_map(|_| {

[1.0_f32, 1.0, 1.0]

.iter()

.flat_map(|f| f.to_le_bytes())

.collect::<Vec<u8>>()

})

.collect();

particles_emit(

burst,

vec![

(position_attr, position_bytes),

(color_attr, color_bytes),

(scale_attr, one_scale),

(age_attr, zero_floats),

(life_attr, one_floats),

)?;

compute_set(

aging,

"params",

shader_value::ShaderValue::Float4([dt, ttl, 0.0, 0.0]),

)?;

particles_apply(p, aging)?;

frame += 1;

}

Ok(())

}

fn hsv_to_rgb(h: f32, s: f32, v: f32) -> (f32, f32, f32) {

let i = (h * 6.0).floor();

let f = h * 6.0 - i;

let p = v * (1.0 - s);

let q = v * (1.0 - f * s);

let t = v * (1.0 - (1.0 - f) * s);

match (i as i32) % 6 {

0 => (v, t, p),

1 => (q, v, p),

2 => (p, v, t),

3 => (p, q, v),

4 => (t, p, v),

_ => (v, p, q),

}