testgesture.c File Reference

#include "SDL.h"
#include <stdlib.h>
#include "SDL_test.h"
#include "SDL_test_common.h"

Include dependency graph for testgesture.c:

Go to the source code of this file.

Data Structures
struct	Point
struct	Knob

Macros
#define	WIDTH   640
#define	HEIGHT   480
#define	BPP   4
#define	EVENT_BUF_SIZE   256
#define	VERBOSE   0

Functions
static void	setpix (SDL_Surface *screen, float _x, float _y, unsigned int col)
static void	drawLine (SDL_Surface *screen, float x0, float y0, float x1, float y1, unsigned int col)
static void	drawCircle (SDL_Surface *screen, float x, float y, float r, unsigned int c)
static void	drawKnob (SDL_Surface *screen, const Knob *k)
static void	DrawScreen (SDL_Window *window)
static void	loop (void)
int	main (int argc, char *argv[])

Variables
static SDLTest_CommonState *	state
static SDL_Event	events [EVENT_BUF_SIZE]
static int	eventWrite
static int	colors [7] = {0xFF,0xFF00,0xFF0000,0xFFFF00,0x00FFFF,0xFF00FF,0xFFFFFF}
static int	quitting = 0
static Knob	knob = { 0.0f, 0.1f, { 0.0f, 0.0f } }

Macro Definition Documentation

BPP

#define BPP   4

Definition at line 31 of file testgesture.c.

EVENT_BUF_SIZE

#define EVENT_BUF_SIZE   256

Definition at line 34 of file testgesture.c.

HEIGHT

#define HEIGHT   480

Definition at line 30 of file testgesture.c.

VERBOSE

#define VERBOSE   0

Definition at line 36 of file testgesture.c.

WIDTH

#define WIDTH   640

Definition at line 29 of file testgesture.c.

Function Documentation

drawCircle()

static void drawCircle ( SDL_Surface *  screen, float  x, float  y, float  r, unsigned int  c  )

static

Definition at line 103 of file testgesture.c.

{
    float tx,ty, xr;
    for (ty = (float) -SDL_fabs(r); ty <= (float) SDL_fabs((int) r); ty++) {
        xr = (float) SDL_sqrt(r * r - ty * ty);
        if (r > 0) { /* r > 0 ==> filled circle */
            for(tx = -xr + 0.5f; tx <= xr - 0.5f; tx++) {
                setpix(screen, x + tx, y + ty, c);
            }
        } else {
            setpix(screen, x - xr + 0.5f, y + ty, c);
            setpix(screen, x + xr - 0.5f, y + ty, c);
        }
    }
}

References screen, SDL_fabs, SDL_sqrt, and setpix().

Referenced by drawKnob(), and DrawScreen().

drawKnob()

static void drawKnob ( SDL_Surface *  screen, const Knob *  k  )

static

Definition at line 120 of file testgesture.c.

{
    drawCircle(screen, k->p.x * screen->w, k->p.y * screen->h, k->r * screen->w, 0xFFFFFF);
    drawCircle(screen, (k->p.x + k->r / 2 * SDL_cosf(k->ang)) * screen->w,
               (k->p.y + k->r / 2 * SDL_sinf(k->ang)) * screen->h, k->r / 4 * screen->w, 0);
}

References drawCircle(), k, screen, SDL_cosf, and SDL_sinf.

Referenced by DrawScreen().

drawLine()

static void drawLine ( SDL_Surface *  screen, float  x0, float  y0, float  x1, float  y1, unsigned int  col  )

static

Definition at line 94 of file testgesture.c.

{
    float t;
    for (t = 0; t < 1; t += (float) (1.0f / SDL_max(SDL_fabs(x0 - x1), SDL_fabs(y0 - y1)))) {
        setpix(screen, x1 + t * (x0 - x1), y1 + t * (y0 - y1), col);
    }
}

References screen, SDL_fabs, SDL_max, and setpix().

DrawScreen()

static void DrawScreen ( SDL_Window *  window )

static

Definition at line 128 of file testgesture.c.

{
    SDL_Surface *screen = SDL_GetWindowSurface(window);
    int i;
 
    if (!screen) {
        return;
    }
 
    SDL_FillRect(screen, NULL, SDL_MapRGB(screen->format, 75, 75, 75));
 
    /* draw Touch History */
    for (i = eventWrite; i < eventWrite + EVENT_BUF_SIZE; ++i) {
        const SDL_Event *event = &events[i & (EVENT_BUF_SIZE - 1)];
        const float age = (float)(i - eventWrite) / EVENT_BUF_SIZE;
        float x, y;
        unsigned int c, col;
 
        if ( (event->type == SDL_FINGERMOTION) ||
             (event->type == SDL_FINGERDOWN) ||
             (event->type == SDL_FINGERUP) ) {
            x = event->tfinger.x;
            y = event->tfinger.y;
 
            /* draw the touch: */
            c = colors[event->tfinger.fingerId % 7];
            col = ((unsigned int) (c * (0.1f + 0.85f))) | (unsigned int) (0xFF * age) << 24;
 
            if (event->type == SDL_FINGERMOTION) {
                drawCircle(screen, x * screen->w, y * screen->h, 5, col);
            } else if (event->type == SDL_FINGERDOWN) {
                drawCircle(screen, x * screen->w, y * screen->h, -10, col);
            }
        }
    }
 
    if (knob.p.x > 0) {
        drawKnob(screen, &knob);
    }
 
    SDL_UpdateWindowSurface(window);
}

References colors, drawCircle(), drawKnob(), EVENT_BUF_SIZE, events, eventWrite, i, knob, NULL, Knob::p, screen, SDL_FillRect, SDL_FINGERDOWN, SDL_FINGERMOTION, SDL_FINGERUP, SDL_GetWindowSurface, SDL_MapRGB, SDL_UpdateWindowSurface, and Point::x.

Referenced by loop().

loop()

static void loop ( void  )

static

Definition at line 172 of file testgesture.c.

{
    SDL_Event event;
    SDL_RWops *stream;
    int i;
 
    while (SDL_PollEvent(&event)) {
        SDLTest_CommonEvent(state, &event, &quitting);
 
        /* Record _all_ events */
        events[eventWrite & (EVENT_BUF_SIZE-1)] = event;
        eventWrite++;
 
        switch (event.type) {
            case SDL_KEYDOWN:
                switch (event.key.keysym.sym) {
                    case SDLK_i: {
                        for (i = 0; i < SDL_GetNumTouchDevices(); ++i) {
                            const SDL_TouchID id = SDL_GetTouchDevice(i);
                            SDL_Log("Fingers Down on device %"SDL_PRIs64": %d", id, SDL_GetNumTouchFingers(id));
                        }
                        break;
                    }
 
                    case SDLK_SPACE:
                        SDL_RecordGesture(-1);
                        break;
 
                    case SDLK_s:
                        stream = SDL_RWFromFile("gestureSave", "w");
                        SDL_Log("Wrote %i templates", SDL_SaveAllDollarTemplates(stream));
                        SDL_RWclose(stream);
                        break;
 
                    case SDLK_l:
                        stream = SDL_RWFromFile("gestureSave", "r");
                        SDL_Log("Loaded: %i", SDL_LoadDollarTemplates(-1, stream));
                        SDL_RWclose(stream);
                        break;
                }
                break;
 
#if VERBOSE
            case SDL_FINGERMOTION:
                SDL_Log("Finger: %"SDL_PRIs64",x: %f, y: %f",event.tfinger.fingerId,
                        event.tfinger.x,event.tfinger.y);
                break;
 
            case SDL_FINGERDOWN:
                SDL_Log("Finger: %"SDL_PRIs64" down - x: %f, y: %f",
                        event.tfinger.fingerId,event.tfinger.x,event.tfinger.y);
                break;
 
            case SDL_FINGERUP:
                SDL_Log("Finger: %"SDL_PRIs64" up - x: %f, y: %f",
                        event.tfinger.fingerId,event.tfinger.x,event.tfinger.y);
                break;
#endif
 
            case SDL_MULTIGESTURE:
#if VERBOSE
                SDL_Log("Multi Gesture: x = %f, y = %f, dAng = %f, dR = %f",
                        event.mgesture.x, event.mgesture.y,
                        event.mgesture.dTheta, event.mgesture.dDist);
                SDL_Log("MG: numDownTouch = %i",event.mgesture.numFingers);
#endif
 
                knob.p.x = event.mgesture.x;
                knob.p.y = event.mgesture.y;
                knob.ang += event.mgesture.dTheta;
                knob.r += event.mgesture.dDist;
                break;
 
            case SDL_DOLLARGESTURE:
                SDL_Log("Gesture %"SDL_PRIs64" performed, error: %f",
                        event.dgesture.gestureId, event.dgesture.error);
                break;
 
            case SDL_DOLLARRECORD:
                SDL_Log("Recorded gesture: %"SDL_PRIs64"",event.dgesture.gestureId);
                break;
        }
    }
 
    for (i = 0; i < state->num_windows; ++i) {
        if (state->windows[i]) {
            DrawScreen(state->windows[i]);
        }
    }
 
#ifdef __EMSCRIPTEN__
    if (quitting) {
        emscripten_cancel_main_loop();
    }
#endif
}

References Knob::ang, DrawScreen(), EVENT_BUF_SIZE, events, eventWrite, i, knob, SDLTest_CommonState::num_windows, Knob::p, quitting, Knob::r, SDL_DOLLARGESTURE, SDL_DOLLARRECORD, SDL_FINGERDOWN, SDL_FINGERMOTION, SDL_FINGERUP, SDL_GetNumTouchDevices, SDL_GetNumTouchFingers, SDL_GetTouchDevice, SDL_KEYDOWN, SDL_LoadDollarTemplates, SDL_Log, SDL_MULTIGESTURE, SDL_PollEvent, SDL_PRIs64, SDL_RecordGesture, SDL_RWclose, SDL_RWFromFile, SDL_SaveAllDollarTemplates, SDLK_i, SDLK_l, SDLK_s, SDLK_SPACE, SDLTest_CommonEvent(), state, SDLTest_CommonState::windows, Point::x, and Point::y.

Referenced by main().

main()

int main	(	int	argc,
		char *	argv[]
	)

Definition at line 269 of file testgesture.c.

{
    state = SDLTest_CommonCreateState(argv, SDL_INIT_VIDEO);
    if (!state) {
        return 1;
    }
 
    state->window_title = "Gesture Test";
    state->window_w = WIDTH;
    state->window_h = HEIGHT;
    state->skip_renderer = SDL_TRUE;
 
    if (!SDLTest_CommonDefaultArgs(state, argc, argv) || !SDLTest_CommonInit(state)) {
        SDLTest_CommonQuit(state);
        return 1;
    }
 
#ifdef __EMSCRIPTEN__
    emscripten_set_main_loop(loop, 0, 1);
#else
    while (!quitting) {
        loop();
    }
#endif
 
    SDLTest_CommonQuit(state);
    return 0;
}

References HEIGHT, loop(), quitting, SDL_INIT_VIDEO, SDL_TRUE, SDLTest_CommonCreateState(), SDLTest_CommonDefaultArgs(), SDLTest_CommonInit(), SDLTest_CommonQuit(), SDLTest_CommonState::skip_renderer, state, WIDTH, SDLTest_CommonState::window_h, SDLTest_CommonState::window_title, and SDLTest_CommonState::window_w.

setpix()

static void setpix ( SDL_Surface *  screen, float  _x, float  _y, unsigned int  col  )

static

Definition at line 59 of file testgesture.c.

{
    Uint32 *pixmem32;
    Uint32 colour;
    Uint8 r, g, b;
    const int x = (int)_x;
    const int y = (int)_y;
    float a;
 
    if ( (x < 0) || (x >= screen->w) || (y < 0) || (y >= screen->h) ) {
        return;
    }
 
    pixmem32 = (Uint32 *) screen->pixels + y * screen->pitch / BPP + x;
 
    SDL_memcpy(&colour, pixmem32, screen->format->BytesPerPixel);
 
    SDL_GetRGB(colour,screen->format,&r,&g,&b);
 
    /* r = 0;g = 0; b = 0; */
    a = (float) ((col >> 24) & 0xFF);
    if (a == 0) {
        a = 0xFF; /* Hack, to make things easier. */
    }
 
    a = (a == 0.0f) ? 1 : (a / 255.0f);
    r = (Uint8) (r * (1 - a) + ((col >> 16) & 0xFF) * a);
    g = (Uint8) (g * (1 - a) + ((col >> 8) & 0xFF) * a);
    b = (Uint8) (b * (1 - a) + ((col >> 0) & 0xFF) * a);
    colour = SDL_MapRGB(screen->format, r, g, b);
 
    *pixmem32 = colour;
}

References BPP, screen, SDL_GetRGB, SDL_MapRGB, and SDL_memcpy.

Referenced by drawCircle(), and drawLine().

Variable Documentation

colors

int colors[7] = {0xFF,0xFF00,0xFF0000,0xFFFF00,0x00FFFF,0xFF00FF,0xFFFFFF}

static

Definition at line 41 of file testgesture.c.

Referenced by DrawScreen(), MapNto1(), SDL_DitherColors(), SDL_LoadBMP_RW(), SDL_SaveBMP_RW(), and SDL_SetPaletteColors().

events

SDL_Event events[EVENT_BUF_SIZE]

static

Definition at line 39 of file testgesture.c.

Referenced by DrawScreen(), IsSDLWindowEventPending(), loop(), SDL_PeepEvents(), UpdateEventsForDeviceRemoval(), and VULKAN_HPP_NAMESPACE::CommandBuffer::waitEvents().

eventWrite

int eventWrite

static

Definition at line 40 of file testgesture.c.

Referenced by DrawScreen(), and loop().

knob

Knob knob = { 0.0f, 0.1f, { 0.0f, 0.0f } }

static

Definition at line 55 of file testgesture.c.

Referenced by DrawScreen(), and loop().

quitting

int quitting = 0

static

Definition at line 42 of file testgesture.c.

Referenced by loop(), and main().

state

SDLTest_CommonState* state

static

Definition at line 38 of file testgesture.c.

Referenced by loop(), and main().