import gg import gx import runtime import time const pwidth = 800 const pheight = 600 const zoom_factor = 1.1 struct ViewRect { mut: x_min f64 x_max f64 y_min f64 y_max f64 } struct AppState { mut: gg &gg.Context = 0 iidx int pixels [pheight][pwidth]u32 npixels [pheight][pwidth]u32 // all drawing happens here, results are copied with vmemcpy to pixels at the end view ViewRect = ViewRect{-2.7610033817025625, 1.1788897130338223, -1.824584023871934, 2.1153096311072788} ntasks int = runtime.nr_jobs() } const colors = [gx.black, gx.blue, gx.red, gx.green, gx.yellow, gx.orange, gx.purple, gx.white, gx.indigo, gx.violet, gx.black] fn (mut state AppState) update() { mut sw := time.new_stopwatch() mut oview := ViewRect{} for { sw.restart() cview := state.view if oview == cview { time.sleep(5 * time.millisecond) continue } sheight := pheight / state.ntasks mut threads := []thread{} for start := 0; start < pheight; start += sheight { threads << go state.recalc_lines(cview, start, start + sheight) } threads.wait() unsafe { vmemcpy(&state.pixels[0], &state.npixels[0], int(sizeof(state.pixels))) } println('$state.ntasks threads; $sw.elapsed().milliseconds() ms / frame') oview = cview } } fn (mut state AppState) recalc_lines(cview ViewRect, ymin f64, ymax f64) { for y_pixel := ymin; y_pixel < ymax && y_pixel < pheight; y_pixel++ { y0 := (y_pixel / pheight) * (cview.y_max - cview.y_min) + cview.y_min for x_pixel := 0.0; x_pixel < pwidth; x_pixel++ { x0 := (x_pixel / pwidth) * (cview.x_max - cview.x_min) + cview.x_min mut x, mut y := x0, y0 mut iter := 0 for ; iter < 80; iter++ { x, y = x * x - y * y + x0, 2 * x * y + y0 if x * x + y * y > 4 { break } } state.npixels[int(y_pixel)][int(x_pixel)] = u32(colors[iter % 8].abgr8()) } } } fn (mut state AppState) draw() { mut istream_image := state.gg.get_cached_image_by_idx(state.iidx) istream_image.update_pixel_data(&state.pixels) size := gg.window_size() state.gg.draw_image(0, 0, size.width, size.height, istream_image) } fn (mut state AppState) zoom(zoom_factor f64) { c_x, c_y := (state.view.x_max + state.view.x_min) / 2, (state.view.y_max + state.view.y_min) / 2 d_x, d_y := c_x - state.view.x_min, c_y - state.view.y_min state.view.x_min = c_x - zoom_factor * d_x state.view.x_max = c_x + zoom_factor * d_x state.view.y_min = c_y - zoom_factor * d_y state.view.y_max = c_y + zoom_factor * d_y } fn (mut state AppState) center(s_x f64, s_y f64) { c_x, c_y := (state.view.x_max + state.view.x_min) / 2, (state.view.y_max + state.view.y_min) / 2 d_x, d_y := c_x - state.view.x_min, c_y - state.view.y_min state.view.x_min = s_x - d_x state.view.x_max = s_x + d_x state.view.y_min = s_y - d_y state.view.y_max = s_y + d_y } // gg callbacks: fn graphics_init(mut state AppState) { state.iidx = state.gg.new_streaming_image(pwidth, pheight, 4, pixel_format: .rgba8) } fn graphics_frame(mut state AppState) { state.gg.begin() state.draw() state.gg.end() } fn graphics_click(x f32, y f32, btn gg.MouseButton, mut state AppState) { if btn == .right { size := gg.window_size() m_x := (x / size.width) * (state.view.x_max - state.view.x_min) + state.view.x_min m_y := (y / size.height) * (state.view.y_max - state.view.y_min) + state.view.y_min state.center(m_x, m_y) } } fn graphics_move(x f32, y f32, mut state AppState) { if state.gg.mouse_buttons.has(.left) { size := gg.window_size() d_x := (f64(state.gg.mouse_dx) / size.width) * (state.view.x_max - state.view.x_min) d_y := (f64(state.gg.mouse_dy) / size.height) * (state.view.y_max - state.view.y_min) state.view.x_min -= d_x state.view.x_max -= d_x state.view.y_min -= d_y state.view.y_max -= d_y } } fn graphics_scroll(e &gg.Event, mut state AppState) { state.zoom(if e.scroll_y < 0 { zoom_factor } else { 1 / zoom_factor }) } fn graphics_keydown(code gg.KeyCode, mod gg.Modifier, mut state AppState) { s_x := (state.view.x_max - state.view.x_min) / 5 s_y := (state.view.y_max - state.view.y_min) / 5 // movement mut d_x, mut d_y := 0.0, 0.0 if code == .enter { println('> $state.view.x_min | $state.view.x_max | $state.view.y_min | $state.view.y_max') } if state.gg.pressed_keys[int(gg.KeyCode.left)] { d_x -= s_x } if state.gg.pressed_keys[int(gg.KeyCode.right)] { d_x += s_x } if state.gg.pressed_keys[int(gg.KeyCode.up)] { d_y -= s_y } if state.gg.pressed_keys[int(gg.KeyCode.down)] { d_y += s_y } state.view.x_min += d_x state.view.x_max += d_x state.view.y_min += d_y state.view.y_max += d_y // zoom in/out if state.gg.pressed_keys[int(gg.KeyCode.left_bracket)] || state.gg.pressed_keys[int(gg.KeyCode.z)] { state.zoom(1 / zoom_factor) return } if state.gg.pressed_keys[int(gg.KeyCode.right_bracket)] || state.gg.pressed_keys[int(gg.KeyCode.x)] { state.zoom(zoom_factor) return } } fn main() { mut state := &AppState{} state.gg = gg.new_context( width: 800 height: 600 create_window: true window_title: 'The Mandelbrot Set' init_fn: graphics_init frame_fn: graphics_frame click_fn: graphics_click move_fn: graphics_move keydown_fn: graphics_keydown scroll_fn: graphics_scroll user_data: state ) go state.update() state.gg.run() }