Files
padlab/analogue.c

389 lines
9.1 KiB
C

#include <SDL.h>
#include <stdio.h>
#include <stdbool.h>
#include <math.h>
#define CAPTIION "Analogue"
#define WINDOW_WIDTH 512
#define WINDOW_HEIGHT 288
#define DISPLAY_SCALE 0.8889
SDL_Window* window = NULL;
SDL_Renderer* rend = NULL;
SDL_JoystickID joyid = -1;
SDL_GameController* pad = NULL;
typedef double vec_t;
typedef struct {vec_t x, y;} vector;
static inline vector VecAdd(vector l, vector r)
{
return (vector){l.x + r.x, l.y + r.y};
}
static inline vector VecScale(vector v, vec_t x)
{
return (vector){v.x * x, v.y * x};
}
static inline double pfmod(double x, double d)
{
return fmod(fmod(x, d) + d, (d));
}
bool UseGamepad(int a_joyid)
{
pad = SDL_GameControllerOpen(a_joyid);
joyid = SDL_JoystickGetDeviceInstanceID(a_joyid);
if (pad != NULL)
{
printf("using gamepad #%d, \"%s\"\n", a_joyid, SDL_GameControllerName(pad));
return true;
}
return false;
}
void DrawCircle(int x, int y, int r, int steps)
{
double stepsz = (M_PI * 2.0) / steps;
int lastx = r;
int lasty = 0;
for (int i = 0; i <= steps; ++i)
{
const double mag = (double)r;
int ofsx = (int)round(cos(stepsz * i) * mag);
int ofsy = (int)round(sin(stepsz * i) * mag);
SDL_RenderDrawLine(rend,
x + lastx, y + lasty,
x + ofsx, y + ofsy);
lastx = ofsx;
lasty = ofsy;
}
}
vector RadialDeadzone(vector v, double min, double max)
{
double mag = sqrt(v.x * v.x + v.y * v.y);
if (mag == 0.0 || mag < min)
{
return (vector){0.0, 0.0};
}
else if (mag > max)
{
return (vector){v.x / mag, v.y / mag};
}
else
{
double rescale = (mag - min) / (max - min);
return (vector){v.x / mag * rescale, v.y / mag * rescale};
}
}
vector DigitalEight(vector v, double deadzone)
{
vector res = {0, 0};
if (fabs(v.x) > fabs(v.y * 2.0))
{
if (fabs(v.x) > deadzone)
res.x = copysign(1.0, v.x);
}
else if (fabs(v.y) > fabs(v.x * 2.0))
{
if (fabs(v.y) > deadzone)
res.y = copysign(1.0, v.y);
}
else if (fabs(v.x) + fabs(v.y) > deadzone * 1.5)
{
const double dscale = 1/sqrt(2);
res.x = copysign(dscale, v.x);
res.y = copysign(dscale, v.y);
}
return res;
}
static inline double AccelCurve(double x, double y)
{
return (x * (x + y)) / (1.0 + y);
}
vector ApplyAcceleration(vector v, double y)
{
double mag = sqrt(v.x * v.x + v.y * v.y);
if (mag > 0.0)
{
double curve = AccelCurve(mag, y);
return (vector){v.x / mag * curve, v.y / mag * curve};
}
else
{
return (vector){0.0, 0.0};
}
}
int main(int argc, char** argv)
{
int res;
res = SDL_Init(SDL_INIT_VIDEO | SDL_INIT_GAMECONTROLLER);
if (res < 0)
goto error;
const int winpos = SDL_WINDOWPOS_CENTERED;
int winw = WINDOW_WIDTH;
int winh = WINDOW_HEIGHT;
window = SDL_CreateWindow(CAPTIION, winpos, winpos, winw, winh, SDL_WINDOW_RESIZABLE);
if (window == NULL)
{
res = -1;
goto error;
}
rend = SDL_CreateRenderer(window, -1, SDL_RENDERER_PRESENTVSYNC);
if (rend == NULL)
{
res = -1;
goto error;
}
if ((res = SDL_GameControllerAddMappingsFromFile("gamecontrollerdb.txt")) != -1)
printf("read %d mappings from gamecontrollerdb.txt\n", res);
for (int i = 0; i < SDL_NumJoysticks(); ++i)
{
if (SDL_IsGameController(i))
{
if (UseGamepad(i))
break;
}
}
vector plrpos = {10.0, 10.0};
vector rawpos = {0.0, 0.0};
vector compos = {0.0, 0.0};
double preaccel = 0.0, postacel = 0.0;
double accelpow = 1.25;
double deadzone = 0.125;
bool running = true;
bool recalcs = true;
bool repaint = true;
bool avatare = false;
uint32_t tickslast = SDL_GetTicks();
while (running)
{
const uint32_t ticks = SDL_GetTicks();
double framedelta = (double)(ticks - tickslast);
tickslast = ticks;
SDL_Event event;
bool onevent = false;
if (!avatare || (compos.x == 0.0 && compos.y == 0.0))
{
onevent = SDL_WaitEvent(&event) != 0;
}
else
{
onevent = SDL_PollEvent(&event) > 0;
repaint = true;
}
if (onevent)
{
do
{
switch (event.type)
{
case (SDL_KEYDOWN):
if (event.key.keysym.sym == SDLK_ESCAPE)
{
running = false;
}
else if (event.key.keysym.sym == SDLK_e)
{
avatare = !avatare;
repaint = true;
}
break;
case (SDL_QUIT):
running = false;
break;
case (SDL_WINDOWEVENT):
if (event.window.event == SDL_WINDOWEVENT_SIZE_CHANGED)
{
winw = event.window.data1;
winh = event.window.data2;
repaint = true;
}
else if (event.window.event == SDL_WINDOWEVENT_EXPOSED)
{
repaint = true;
}
break;
case (SDL_CONTROLLERAXISMOTION):
if (event.caxis.which == joyid)
{
if (event.caxis.axis == SDL_CONTROLLER_AXIS_RIGHTX)
{
rawpos.x = (vec_t)event.caxis.value / (vec_t)0x7FFF;
repaint = recalcs = true;
}
else if (event.caxis.axis == SDL_CONTROLLER_AXIS_RIGHTY)
{
rawpos.y = (vec_t)event.caxis.value / (vec_t)0x7FFF;
repaint = recalcs = true;
}
}
break;
case (SDL_MOUSEMOTION):
if (event.motion.state & SDL_BUTTON_LMASK)
{
rawpos.x = ((double)event.motion.x - winw / 2.0) / (winh * DISPLAY_SCALE / 2.0);
rawpos.y = ((double)event.motion.y - winh / 2.0) / (winh * DISPLAY_SCALE / 2.0);
repaint = recalcs = true;
}
else if (event.motion.state & SDL_BUTTON_RMASK)
{
double scale = 1.0 - ((double)event.motion.y / (double)winh);
//accelpow = scale * scale * scale * 32;
accelpow = pow(scale * 3, 1.0 + scale * 3);
repaint = recalcs = true;
}
case (SDL_CONTROLLERDEVICEADDED):
if (pad == NULL)
UseGamepad(event.cdevice.which);
break;
case (SDL_CONTROLLERDEVICEREMOVED):
if (pad != NULL && event.cdevice.which == joyid)
{
SDL_GameControllerClose(pad);
pad = NULL;
printf("active gamepad was removed\n");
}
break;
default:
break;
}
}
while (SDL_PollEvent(&event) > 0);
}
if (recalcs)
{
compos = RadialDeadzone(rawpos, deadzone, 0.99);
//compos = DigitalEight(rawpos, 0.5);
preaccel = sqrt(compos.x * compos.x + compos.y * compos.y);
compos = ApplyAcceleration(compos, accelpow);
postacel = sqrt(compos.x * compos.x + compos.y * compos.y);
recalcs = false;
}
if (repaint)
{
SDL_Rect rect;
double size = (double)(winw > winh ? winh : winw) * DISPLAY_SCALE;
// background
SDL_SetRenderDrawColor(rend, 0x1F, 0x1F, 0x1F, 0xFF);
SDL_RenderClear(rend);
// test player thingo
if (avatare)
{
plrpos = VecAdd(plrpos, VecScale(compos, framedelta * 0.5));
plrpos.x = pfmod(plrpos.x, winw);
plrpos.y = pfmod(plrpos.y, winh);
SDL_SetRenderDrawColor(rend, 0xFF, 0x00, 0x00, 0xFF);
rect.w = rect.h = 32;
rect.x = (int)plrpos.x - rect.w / 2;
rect.y = (int)plrpos.y - rect.h / 2;
SDL_RenderDrawRect(rend, &rect);
}
// range rect
SDL_SetRenderDrawColor(rend, 0x3F, 0x3F, 0x3F, 0xFF);
rect.w = rect.h = (int)round(size);
rect.x = (winw - rect.w) / 2;
rect.y = (winh - rect.h) / 2;
SDL_RenderDrawRect(rend, &rect);
// acceleration curve
SDL_SetRenderDrawColor(rend, 0x4F, 0x4F, 0x4F, 0xFF);
const int accelsamp = (int)(sqrt(size) * 4.20);
double step = 1.0 / (double)accelsamp;
double y1 = AccelCurve(0.0, accelpow);
for (int i = 1; i <= accelsamp; ++i)
{
double y2 = AccelCurve(step * i, accelpow);
SDL_RenderDrawLine(rend,
(int)(step * (i - 1) * size) + (winw - (int)round(size)) / 2,
(int)((1.0 - y1) * size) + (winh - (int)round(size)) / 2,
(int)(step * i * size) + (winw - (int)round(size)) / 2,
(int)((1.0 - y2) * size) + (winh - (int)round(size)) / 2);
y1 = y2;
}
int tickerx = (int)((preaccel - 0.5) * size);
int tickery = (int)((0.5 - postacel) * size);
SDL_SetRenderDrawColor(rend, 0x2F, 0x3F, 0x1F, 0xFF);
SDL_RenderDrawLine(rend,
winw / 2 + tickerx,
(winh - (int)round(size)) / 2,
winw / 2 + tickerx,
(winh + (int)round(size)) / 2);
SDL_SetRenderDrawColor(rend, 0x2F, 0x5F, 0x2F, 0xFF);
SDL_RenderDrawLine(rend,
(winw - (int)round(size)) / 2,
winh / 2 + tickery,
(winw + (int)round(size)) / 2,
winh / 2 + tickery);
// guide circle
SDL_SetRenderDrawColor(rend, 0x4F, 0x4F, 0x4F, 0xFF);
DrawCircle(winw / 2, winh / 2, (int)round(size) / 2, (int)(sqrt(size) * 8.0));
SDL_SetRenderDrawColor(rend, 0x3F, 0x3F, 0x3F, 0xFF);
DrawCircle(winw / 2, winh / 2, (int)round(deadzone * size) / 2, (int)(sqrt(size) * 2.0));
// 0,0 line axis'
SDL_SetRenderDrawColor(rend, 0x2F, 0x2F, 0x2F, 0xFF);
SDL_RenderDrawLine(rend, 0, winh / 2, winw, winh / 2);
SDL_RenderDrawLine(rend, winw / 2, 0, winw / 2, winh);
// compensated position
SDL_SetRenderDrawColor(rend, 0x1F, 0xFF, 0x1F, 0xFF);
DrawCircle(
winw / 2 + (int)round(compos.x * size / 2.0),
winh / 2 + (int)round(compos.y * size / 2.0),
4, 8);
// raw position
SDL_SetRenderDrawColor(rend, 0xFF, 0xFF, 0xFF, 0xFF);
DrawCircle(
winw / 2 + (int)round(rawpos.x * size / 2.0),
winh / 2 + (int)round(rawpos.y * size / 2.0),
8, 16);
SDL_RenderPresent(rend);
repaint = false;
}
}
res = 0;
error:
SDL_GameControllerClose(pad);
SDL_DestroyRenderer(rend);
SDL_DestroyWindow(window);
SDL_Quit();
return res;
}