2c:null 2d:["$","title",null,{"children":"Piangle for Anna <3 | emma-ba | Observable"}] 32:Tb20,anna = { // Fractal pine trees on a mountain lake const col = ['#00f','#000','#606','#666','#0f0','#09f','#930','#f60','#f0f','#fff']; const col_down = ['#00f','#090','#c0c','#ccc','#0f0','#09f','#c60','#f93','#f0f','#fff']; const u = 1.5; // unit const wu = 400; // no. units on width const hu = 400; // no. units on height const width = wu*u*2; // double the units to have spaces between squares const height = hu*u*2; // double the units to have bottom & top piangles const margin = 2*20; const board_height = height; //1000*5.5; const board_width = width; //1414*5.5; let data_top, data_down, new_top, new_down, r, l, x, y, digit_top, digit_down; let ray = 0.7; let trans_x = (board_width - width)/2; let trans_y = (board_height - height)/2; // Background const { canvas, context } = createCanvas(); const pixelRatio = resize(canvas, board_width + 2*margin, board_height + 2*margin, ); context.globalAlpha = 1; context.scale(pixelRatio, pixelRatio); context.fillStyle = '#000'; context.fillRect(0, 0, board_width+2*margin, board_height+2*margin); ///////////////// DATA ///////////////// const base = get_pi_txt(wu+1); data_top = [[]]; data_down = [[]]; data_top[0] = base; data_down[0] = base; for (let h = 1; h < hu; ++h){ data_top[h] = []; data_down[h] = []; for (let w = 1; w < wu; ++w) { if(w > (wu-h)){ new_top = 0; new_down = 0; } else { r = data_top[h-1][w+1]; l = data_top[h-1][w]; new_top = alg_paon(l, r, 2, 10); //thres, modulo r = data_down[h-1][w+1]; l = data_down[h-1][w]; new_down = alg_paon(l, r, 2, 20); } data_top[h][w] = new_top; data_down[h][w] = new_down; } } //////////////////// DRAW //////////////// for (let h = 0; h < hu; ++h){ for (let w = 0; w < wu; ++w) { ///// TOP digit_top = data_top[h][w]; if(digit_top != 0){ x = u*w*2 + h*u + margin/2 + trans_x; y = (hu-h)*u + margin/2 + trans_y; context.fillStyle = col[digit_top]; context.fillRect(x, y, u, u); } ///// DOWN digit_down = Math.round(data_down[h][w])%10; if(digit_down != 0){ if(digit_top == digit_down) { //context.globalAlpha = 1; //context.fillStyle = col[digit_down]; } else if(digit_top == 4 | digit_top == 9 | digit_top == digit_down){ context.globalAlpha = 1; context.fillStyle = col_down[digit_down]; } else { context.globalAlpha = 0.4; context.fillStyle = col[digit_down]; } x = u*w*2 + h*u + margin/2 + trans_x; y = h*u + margin/2 + hu*u + trans_y; context.fillRect(x, y, u, u); } context.globalAlpha = 1; } } return canvas; }33:[{"id":"34efc5064cab74f4007753420692ed31b5de2e67ff7f15f3bdf9787c825e6f5127db64a8063d75bad051c3f5a893b391e1a2f4a5f71c04dfd95d50994915f7d2","href":"https://static.observableusercontent.com/files/34efc5064cab74f4007753420692ed31b5de2e67ff7f15f3bdf9787c825e6f5127db64a8063d75bad051c3f5a893b391e1a2f4a5f71c04dfd95d50994915f7d2","name":"pi.txt","type":"text/plain","lastModified":1680086977822.894,"size":1000002}] 30:{"id":"df833e6518a24770","slug":null,"title":"Piangle for Anna <3","thumbnail":"dcc97bba677322a227cd223683ca06dca162bae95250cfd73b4fe4fefda76f99","access_level":"public","create_time":"$D2023-03-29T10:49:37.822Z","update_time":"$D2023-03-30T09:39:45.041Z","view_time":null,"first_public_time":"$D2023-03-29T10:49:37.822Z","has_unpublished_edits":null,"fork":{"id":"a1b9bf73d1a928dc","slug":"piangle-for-m-c","title":"Piangle for M.C.","owner":{"id":"5d9b00b2cdcd8028","login":"emma-ba","name":""}},"stars":0,"starred":false,"owner":{"type":"team","id":"5d9b00b2cdcd8028","login":"emma-ba","name":"","avatar_url":"https://avatars-next.observableusercontent.com/3950b079ad1fc587c84ccfe712c3cc77ad1e122194ac7deeaf2ea35c7bf0f25a","tier":"starter_2024"},"version":483,"publish_version":null,"role":null,"authored":false,"authors":[{"type":"individual","id":"261e0273bd70e808","login":"emma-ba","name":"","avatar_url":"https://avatars-next.observableusercontent.com/3950b079ad1fc587c84ccfe712c3cc77ad1e122194ac7deeaf2ea35c7bf0f25a","tier":null}],"members":[{"type":"individual","id":"261e0273bd70e808","login":"emma-ba","name":"","avatar_url":"https://avatars-next.observableusercontent.com/3950b079ad1fc587c84ccfe712c3cc77ad1e122194ac7deeaf2ea35c7bf0f25a","tier":null,"role":"editor"}],"comments":[],"custom_thumbnail":false,"trashed":false,"lapsed":null,"subscribed":null,"forks":1,"collection":{"id":"eb707ad90c7cf937","slug":"piangles","title":"Piangles","owner":{"id":"5d9b00b2cdcd8028","login":"emma-ba","name":""}},"type":"notebook","body":{"title":"Piangle for Anna <3","cells":[{"id":0,"value":"# Piangle for Anna <3","pinned":false,"hidden":false,"mode":"md","author":"$undefined","summary":"$undefined","output":"","database":"$undefined"},{"id":167,"value":"$32","pinned":true,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":170,"value":"alg_paon = (l, r, thres, modulo) => {\n let diff = Math.abs(l - r);\n let sum = l + r;\n let new_d = 0;\n\n if(l == r){new_d = r;}\n else if(l%r == 0){new_d = r;}\n else if(r%l == 0){new_d = l;}\n\n if(diff < thres){ new_d = sum ;}\n \n return new_d % modulo;\n}","pinned":true,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":305,"value":"alg_alt = (l, r, power, thres, modulo) => {\n let new_d = (r**power) - (l**power);\n new_d = Math.min( new_d, thres);\n new_d = Math.max( new_d, -1*thres);\n new_d = Math.abs(new_d);\n return new_d % modulo;\n}","pinned":false,"hidden":false,"mode":"ojs","author":"$undefined","summary":"$undefined","output":"$undefined","database":"$undefined"},{"id":7,"value":"get_pi = (length) => {\n const D = Decimal.clone({precision: length+1});\n const one = D(1), four = D(4);\n const a = four.times(arctan(one.div(5)));\n const b = arctan(one.div(239));\n const pi = four.times(a.minus(b));\n const p = pi.toFixed(length); 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