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/* ************************************************************** * C++ Mathematical Expression Toolkit Library * * * * ExprTk Mandelbrot Fractal Generator Example * * Author: Arash Partow (1999-2024) * * URL: https://www.partow.net/programming/exprtk/index.html * * * * Copyright notice: * * Free use of the Mathematical Expression Toolkit Library is * * permitted under the guidelines and in accordance with the * * most current version of the MIT License. * * https://www.opensource.org/licenses/MIT * * SPDX-License-Identifier: MIT * * * ************************************************************** */ #include #include #include "exprtk.hpp" template inline T putch(T v) { printf("%c",static_cast(v)); return T(0); } template void mandelbrot() { typedef exprtk::symbol_table symbol_table_t; typedef exprtk::expression expression_t; typedef exprtk::parser parser_t; const std::string mandelbrot_program = " width := 118; " " height := 41; " " imag_max := +1; " " imag_min := -1; " " real_max := +1; " " real_min := -2.5; " " x_step := (real_max - real_min) / width; " " y_step := (imag_max - imag_min) / height; " " " " for (var y := 0; y < height; y += 1) " " { " " imag := imag_min + (y_step * y); " " " " for (var x := 0; x < width; x += 1) " " { " " real := real_min + x_step * x; " " z_real := real; " " z_imag := imag; " " " " for (var n := 0; n < 30; n += 1) " " { " " a := z_real^2; " " b := z_imag^2; " " plot_value := n; " " " " if ((a + b) < 4) " " { " " z_imag := 2 * z_real * z_imag + imag; " " z_real := a - b + real; " " } " " else " " break; " " }; " " " " putch(61 - plot_value); " " }; " " " " println() " " } "; exprtk::rtl::io::println println; symbol_table_t symbol_table; symbol_table.add_function("putch" , putch ); symbol_table.add_function("println", println); expression_t expression; expression.register_symbol_table(symbol_table); parser_t parser; parser.enable_unknown_symbol_resolver(); parser.compile(mandelbrot_program,expression); expression.value(); } int main() { mandelbrot(); return 0; }