I thought of an easier way to bounds check the game_controller_input union in handmade.h
The original assert for reference
Since game_controller_input is a union, couldn't we copy-pasta the anonymous struct and add an identifier to the end of it?
This way, the assert becomes much more straightforward.
Comparison:
I remember seeing in the MSDN docs somewhere that they did this with one of the structs we used. I'm trying to find info about this technique online but I don't know what it's called... :(
The original assert for reference
1 | Assert((&Input->Controllers[0].Terminator - &Input->Controllers[0].Buttons[0]) == (ArrayCount(Input->Controllers[0].Buttons) - 1)); |
Since game_controller_input is a union, couldn't we copy-pasta the anonymous struct and add an identifier to the end of it?
1 2 3 4 5 6 7 8 9 10 11 12 13 14 15 16 17 18 19 20 21 22 23 24 25 26 27 28 29 30 31 32 33 34 35 36 37 38 39 40 41 42 43 44 45 46 47 48 49 50 | struct game_controller_input
{
bool32 IsConnected;
bool32 IsAnalog;
real32 StickAverageX;
real32 StickAverageY;
union
{
game_button_state Buttons[12];
struct
{
game_button_state MoveUp;
game_button_state MoveDown;
game_button_state MoveLeft;
game_button_state MoveRight;
game_button_state ActionUp;
game_button_state ActionDown;
game_button_state ActionLeft;
game_button_state ActionRight;
game_button_state LeftShoulder;
game_button_state RightShoulder;
game_button_state Back;
game_button_state Start;
};
struct
{
game_button_state MoveUp;
game_button_state MoveDown;
game_button_state MoveLeft;
game_button_state MoveRight;
game_button_state ActionUp;
game_button_state ActionDown;
game_button_state ActionLeft;
game_button_state ActionRight;
game_button_state LeftShoulder;
game_button_state RightShoulder;
game_button_state Back;
game_button_state Start;
} u;
};
};
|
This way, the assert becomes much more straightforward.
Comparison:
1 | Assert((&Input->Controllers[0].Terminator - &Input->Controllers[0].Buttons[0]) == (ArrayCount(Input->Controllers[0].Buttons) - 1)); |
1 | Assert(sizeof(Input->Controllers[0].Buttons) == sizeof(Input->Controllers[0].u)); |
I remember seeing in the MSDN docs somewhere that they did this with one of the structs we used. I'm trying to find info about this technique online but I don't know what it's called... :(
Edited by Salads
on
Why would you want that copy&paste?
Imho that is very ugly. Better way would be to remove first structure, rename u to Button, and use it like "Input->Button.MoveUp.IsDown".
This is called "anonymous structure". You are not giving structure type name, but directly using it for member type.
Imho that is very ugly. Better way would be to remove first structure, rename u to Button, and use it like "Input->Button.MoveUp.IsDown".
This is called "anonymous structure". You are not giving structure type name, but directly using it for member type.
Edited by Mārtiņš Možeiko
on