generative-adversarial-network.typ

#import "@preview/cetz:0.3.2": canvas, draw
#import draw: line, content, circle, group, hobby, on-layer

#set page(width: auto, height: auto, margin: 8pt)

#canvas({
  // Style definitions
  let node-style = (
    stroke: none,
    fill: rgb("#66B2B2"), // teal!60 equivalent
    radius: 0.53,
  )
  let arrow-style = (
    stroke: black + 0.8pt,
    mark: (end: "stealth", scale: 0.4, fill: black),
  )

  let (y-real, y-fake) = (2, 0)

  // Draw nodes
  // z_in node
  circle((0, y-fake), name: "zin", ..node-style)
  content("zin", $arrow(z)_"in"$)

  // x_fake node
  circle((3, y-fake), name: "fake", ..node-style)
  content("fake", $arrow(x)_"fake"$)

  // x_real node
  circle((3, y-real), name: "real", ..node-style)
  content("real", $arrow(x)_"real"$)

  // x node (discriminator input)
  circle((6, y-real / 2), name: "D", ..node-style, radius: 0.4)
  content("D", $arrow(x)$)

  // Output node
  content((9, y-real / 2), text(size: 0.9em, baseline: -1pt)[real?], name: "out", padding: 2pt)

  // Draw arrows and their labels
  // Generator input arrow
  line((-2.5, y-fake), "zin", ..arrow-style, name: "zin-line")
  content("zin-line.mid", $p_theta (arrow(z))$, anchor: "south", padding: 0.1)
  content("zin-line.mid", text(size: 0.8em)[latent noise], anchor: "north", padding: 0.1)

  // Generator arrow
  line("zin", "fake", ..arrow-style, name: "fake-line")
  content("fake-line.mid", $G(arrow(x))$, anchor: "south", padding: 0.1)
  content("fake-line.mid", text(size: 0.8em)[generator], anchor: "north", padding: 0.1)

  // Real data arrow
  line((-2, y-real), "real", ..arrow-style, name: "real-line")
  content("real-line.mid", $p_"data" (arrow(x))$, anchor: "south", padding: 0.1)

  // Connection points with names
  circle((4.5, y-fake), radius: 0.06, fill: black, name: "dot1")
  circle((4.5, y-real), radius: 0.06, fill: black, name: "dot2")
  on-layer(
    1,
    circle((4.25, 2 * y-real / 3), radius: 0.12, fill: orange, stroke: none, name: "dot3"),
  )

  // Draw connecting lines with names
  line("fake", "dot1", ..arrow-style, name: "conn1")
  line("real", "dot2", ..arrow-style, name: "conn2")
  line("dot3", "D", ..arrow-style, name: "conn3")

  // Draw dashed curve using named points
  hobby(
    "dot1",
    (4.2, (y-real - y-fake) / 2),
    "dot2",
    stroke: (dash: "dashed"),
    omega: 2,
    name: "dashed-curve",
  )

  // Discriminator arrow and labels
  line("D", "out", ..arrow-style, name: "disc-line")
  content("disc-line.mid", $D(arrow(x))$, anchor: "south", padding: 0.1)
  content("disc-line.mid", text(size: 0.8em)[discriminator], anchor: "north", padding: 0.15)
})