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/******************************************************************************
 * MAIN.C - Beyaz zemin üzerinde kırmızı kare (D-Pad kontrolü)
 * Psy-Q (SN Systems) örnek.
 ******************************************************************************/
#include <sys/types.h>
#include <libgte.h>
#include <libgpu.h>
#include <libetc.h>

// Ekran boyutu.
#define SCREEN_W 320.
#define SCREEN_H 240.

// Ordering Table boyutu.
#define OT_LENGTH 1

// Ordering Table ve GPU paket alanı.
GsOT ot[OT_LENGTH];
GsOT_TAG ot_tag[1 << OT_LENGTH];
PACKET gpu_packet[16];

// Kırmızı kutunun pozisyonu.
int boxX = 100;
int boxY = 100;
int boxSize = 30;

// Prototipler.
void initGraphics(void);
void drawRedBox(int x, int y, int size);

int main() {
 // Grafik başlat.
 initGraphics();

 // Pad'i başlat.
 InitPAD(0, 0, 0, 0);
 StartPAD();
 ChangeClearPAD(0);

 while (1) {
 // OT temizle.
 ClearOTagR((u_long*)ot[0].ot, 1 << OT_LENGTH);

 // Pad okuyalım.
 // libetc.h fonksiyonu: Poll ve pad butonlarını al.
 PADTYPE p = PadRead(0);
 if (!(p & PADLup)) { boxY -= 2; if(boxY < 0) boxY = 0; }
 if (!(p & PADLdown)) { boxY += 2; if(boxY > SCREEN_H - boxSize) boxY = SCREEN_H - boxSize; }
 if (!(p & PADLleft)) { boxX -= 2; if(boxX < 0) boxX = 0; }
 if (!(p & PADLright)){ boxX += 2; if(boxX > SCREEN_W - boxSize) boxX = SCREEN_W - boxSize; }

 // Kırmızı kutuyu çiz.
 drawRedBox(boxX, boxY, boxSize);

 // Ekrana gönder.
 DrawSync(0);
 VSync(0);
 GsSwapDispBuff();
 GsSortClear(255, 255, 255); // Arka planı beyaz.
 GsDrawOt(&ot[0]);
 }
 return 0;
}

// ----------------------------------------------------------
// Basit grafik init - 320x240 çözünürlük, double-buffer
// ----------------------------------------------------------
void initGraphics(void) {
 ResetGraph(0);
 SetDefDrawEnv(&GsDrawEnv, 0, 0, SCREEN_W, SCREEN_H);
 SetDefDispEnv(&GsDispEnv, 0, 0, SCREEN_W, SCREEN_H);

 // Double buffer.
 GsDrawEnv.isbg = 1; // Arka plan temizleme.
 GsDrawEnv.r0 = 255; // Beyaz R
 GsDrawEnv.g0 = 255; // Beyaz G
 GsDrawEnv.b0 = 255; // Beyaz B

 PutDrawEnv(&GsDrawEnv);
 PutDispEnv(&GsDispEnv);

 // OT hazırla.
 GsClearOt(0, 0, &ot[0]);
 GsSetWorkBase((PACKET*)gpu_packet);
 GsClearWorkBase();
 GsSetVideoMode(VID_MODE_PAL); // Veya VID_MODE_NTSC.
 SetDispMask(1);
}

// ----------------------------------------------------------
// drawRedBox : Kırmızı renkli POLY_F4 çizer.
// ----------------------------------------------------------
void drawRedBox(int x, int y, int size) {
 POLY_F4* poly = (POLY_F4*)GsGetWorkBase();
 GsSetWorkBase((PACKET*)((u_long)poly + sizeof(POLY_F4)));

 setPolyF4(poly);
 setXY4(poly,
 x, y,
 x+size,y,
 x, y+size,
 x+size,y+size);
 setRGB0(poly, 255,0,0); // Kırmızı.
 setShadeTex(poly, 0);
 AddPrim(&ot[0], poly);
}

all : MAIN.EXE

MAIN.EXE : MAIN.OBJ
 C:\PSYQ\BIN\CCPSX.EXE MAIN.OBJ -o MAIN.EXE \
 C:\PSYQ\LIB\LIBETC.LIB C:\PSYQ\LIB\LIBGTE.LIB \
 C:\PSYQ\LIB\LIBGPU.LIB C:\PSYQ\LIB\LIBSPU.LIB
MAIN.OBJ : MAIN.C
 C:\PSYQ\BIN\CCPSX.EXE -c -Xo2 -G0 MAIN.C
clean :
 del MAIN.OBJ
 del MAIN.EXE