float to short cast overflow, C#

float to short cast overflow

//Rextester.Program.Main is the entry point for your code. Don't change it.
//Compiler version 4.0.30319.17929 for Microsoft (R) .NET Framework 4.5

using System;
using System.Collections.Generic;
using System.Linq;
using System.Text.RegularExpressions;

namespace Rextester
{
    public class Program
    {
        static float DoSomething1(float val)
        {
            return Math.Max(Int16.MinValue, Math.Min(Int16.MaxValue, val * (val > 0 ? Int16.MaxValue : -Int16.MinValue)));
        }

static float DoSomething2(float val)
        {
            if (val >= 1.0f) return Int16.MaxValue;
            if (val <= -1.0f) return Int16.MinValue;
            val = val > 0 ? val * Int16.MaxValue : -val * Int16.MinValue;
            return (float) Math.Round(val);
        }

static void DoThings(float stick)
        {
            string fmt = ": {0};-{0}";
            string fmt1 = String.Format(fmt, "0.00");
            string fmt2 = String.Format(fmt, "00000.00");

float ohboy0 = DoSomething1(stick); // Works
            // float ohboy0 = DoSomething2(stick); // Works

float ohboy1 = -1 * ohboy0; // Fails
            // float ohboy1 = DoSomething1(-1 * stick); // Works
            // float ohboy1 = DoSomething2(-1 * stick); // Works

short ohmy0 = (short)ohboy0;
            short ohmy1 = (short)ohboy1;

bool annieareyouokay = (int)ohboy0 == (int)ohmy0 && (int)ohboy1 == (int)ohmy1;

Console.WriteLine("{0" + fmt1 + "} -> ({1" + fmt2 + "}, {2" + fmt2 + "}) -> ({3" + fmt2 + "}, {4" + fmt2 + "}) ? {5}", stick, ohboy0, ohboy1, ohmy0, ohmy1, annieareyouokay);
        }

public static void Main(string[] args)
        {
            Console.WriteLine("{0} ... {1}", Int16.MinValue, Int16.MaxValue);

Console.WriteLine("{0} ... {1}", -Int16.MaxValue, -Int16.MinValue);
            
            // Note the implicit cast
            short min_val = Int16.MinValue;
            Console.WriteLine("({0}) {1} == ({2}) {3} ? {4}", min_val.GetType(), min_val, (-min_val).GetType(), -min_val, min_val == -min_val);
            
            // Force the type to remain short
            short minus_min_val;
            // Compiles
            minus_min_val = (short)-min_val;
            // unchecked { minus_min_val = (short)-Int16.MinValue; }
            // Does not compile
            // minus_min_val = -min_val;
            // minus_min_val = -Int16.MinValue;
            // minus_min_val = (short)-Int16.MinValue;
            // unchecked { minus_min_val = -min_val; }
            // unchecked { minus_min_val = -Int16.MinValue; }
            Console.WriteLine("({0}) {1} == ({2}) {3} ? {4}", min_val.GetType(), min_val, minus_min_val.GetType(), minus_min_val, min_val == minus_min_val);

Console.WriteLine();

for (int i = 95; i < 105; i++)
            {
                DoThings(i / 100.0f);
                DoThings(-i / 100.0f);
            }
        }
    }
}


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