memories: working on tilted plane
This commit is contained in:
Vince Weaver
parent
25436f888a
commit
d6aed2067d
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@ -233,43 +233,25 @@ static short pop(void) {
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/* tilted plane */
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/* DH=Y, DL=X */
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static int fx0(int xx, int yy, int xprime) {
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return 0;
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}
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#if 0
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char ah,al,dh,dl;
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unsigned short temp;
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unsigned short scaled;
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int color;
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ax=0x1329; // mov ax,0x1329 init
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// 0x1329 = 4905? 200*24.5 40*24.5=981=3d5
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al=ax&0xff; ah=(ax>>8)&0xff;
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dl=xprime; dh=yy;
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yy=yy+0x10;//0x29; // add dh,al ; prevent divide overflow
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scaled=((0x3d5/yy)&0xff); // div dh ; reverse divide AL=C/Y'
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color=((signed char)((xprime-20)&0xff))*((signed char)(scaled&0xff));
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dh=dh+al; // add dh,al ; prevent divide overflow
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div_8(dh); // div dh ; reverse divide AL=C/Y'
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scaled-=frame;
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dx=((dh&0xff)<<8)|dl;
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color=(color>>6)&0xff;
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color^=(scaled&0xff);
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color&=0x1c; // map colors
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temp=ax;
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ax=dx; dx=temp; // xchg dx,ax ; DL=C/Y' AL=X
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dl=dx&0xff; dh=(dx>>8)&0xff;
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imul_8(dl); // imul dl
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dx=dx-frame; // sub dx,bp
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dl=dx&0xff;
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ah=(ax>>8)&0xff;
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ah=ah^dl; // xor ah,dl
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al=ah; // mov al,ah
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ax=((ah&0xff)<<8)|(al&0xff);
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ax&=0xff1c; // and al,4+8+16
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return ax;
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return color;
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}
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#endif
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/* circles? */
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/* DH=Y, DL=X */
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static int fx1(int xx, int yy, int xprime) {
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@ -559,7 +541,9 @@ int main(int argc, char **argv) {
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ram[DRAW_PAGE]=0;
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frame=0x13;
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// frame=0x13;
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frame=2*512;
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while(1) {
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for(yy=0;yy<48;yy++) {
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@ -571,12 +555,12 @@ int main(int argc, char **argv) {
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which=frame/512;
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switch (which&0xff) {
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case 0: color=fx5(xx,yy,xprime); break;
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case 0: color=fx2(xx,yy,xprime); break;
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case 1: color=fx1(xx,yy,xprime); break;
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case 2: color=fx0(xx,yy,xprime); break;
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case 3: color=fx3(xx,yy,xprime); break;
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case 4: color=fx4(xx,yy,xprime); break;
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case 5: color=fx2(xx,yy,xprime); break;
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case 5: color=fx5(xx,yy,xprime); break;
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case 6: color=fx6(xx,yy,xprime); break;
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case 7: return 0;
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default: printf("Trying effect %d\n",which);
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@ -210,6 +210,8 @@ static void write_framebuffer(int address, int value) {
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}
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#if 0
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/* unsigned multiply */
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static void mul_16(unsigned short value) {
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unsigned int result;
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@ -238,7 +240,9 @@ static void mul_16(unsigned short value) {
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}
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/*
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#endif
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/*
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static void imul(short value) {
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int result;
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@ -355,7 +359,7 @@ static void imul_16_dx(short value) {
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#if 0
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/* unsigned divide */
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static void div_8(unsigned char value) {
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@ -382,7 +386,7 @@ static void div_8(unsigned char value) {
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}
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#endif
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static void push(int value) {
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//printf("Pushing %x\n",value);
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@ -407,35 +411,19 @@ static short pop(void) {
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/* DH=Y, DL=X */
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static int fx0(int xx, int yy, int xprime) {
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char ah,al,dh,dl;
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unsigned short temp;
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unsigned short scaled;
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int color;
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ax=0x1329; // mov ax,0x1329 init
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al=0x29; ah=0x13;
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dl=xprime; dh=yy;
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yy=yy+0x29; // add dh,al ; prevent divide overflow
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scaled=((0x1329/yy)&0xff); // div dh ; reverse divide AL=C/Y'
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color=((signed char)(xprime&0xff))*((signed char)(scaled&0xff));
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dh=dh+al; // add dh,al ; prevent divide overflow
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div_8(dh); // div dh ; reverse divide AL=C/Y'
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scaled-=frame;
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dx=((dh&0xff)<<8)|dl;
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temp=ax;
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ax=dx; dx=temp; // xchg dx,ax ; DL=C/Y' AL=X
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dl=dx&0xff; dh=(dx>>8)&0xff;
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imul_8(dl); // imul dl
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dx=dx-frame; // sub dx,bp
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dl=dx&0xff;
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ah=(ax>>8)&0xff;
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ah=ah^dl; // xor ah,dl
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al=ah; // mov al,ah
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color=((ah&0xff)<<8)|(al&0xff);
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color&=0x1c; // and al,4+8+16
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color=(color>>8)&0xff;
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color^=(scaled&0xff);
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color&=0x1c; // map colors
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return color;
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}
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@ -679,6 +667,68 @@ fx6q: ;
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}
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/* raycast bent tunnel */
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/* no multiply */
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static int fx7(int xx, int yy, int xprime) {
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#if 0
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unsigned char al,ah,bl,bh,cl,dl,dh,tb=0;
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unsigned short bp;
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// dx=((yy&0xff)<<8) | (xprime&0xff);
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// dx=y
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// bp=x
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dh=0;
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dl=yy; // xor dx,dx
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bp=xprime;
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cl=80; // mov cl,80
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ch=0; // mov ch,0
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ah=0; // xor ax,ax
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al=0;
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bh=0; // xor bx,bx
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bx=0;
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L:
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ch=ch-dh; // sub ch,dh ah/ch = x
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ah=ah-0-cf; // sbb ah,0
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ch=ch+cl; // add ch,cl bend with depth
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ah=ah+0+cf; // adc ah,0
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bl=bl-dl; // sub bl,dl bh/bl=y
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bh=bh-0-cf; // sbb bh,0
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bl=bl+cl; // add bl,cl bend with depth
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bh=bh+0+cf; // adc bh,0
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bl=bl+cl; // add bl,cl bend with depth
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bh=bh+0+cf; // adc bh,0
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al=bh; // mov al,bh leave ah,bh untouched
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al=al^ah; // xor al,ah geometry check
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al+=4; // add al,4 geometry check
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// test al,8 geometry check
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// jnz Q
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if (al&8!=0) goto Q;
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cl--; // dec cl
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if (cl!=0) goto L;
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if ((cl!=0) && (zf==1)) goto L; // loopz L
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Q:
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cl=cl-frame; // probably the timer sub cl,[0x46c]
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al=al^cl; // xor al,cl
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// aam 6
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al=al+20; // add al,20
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// stosb
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#endif
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return ax;
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}
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int main(int argc, char **argv) {
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int color=0,which,xx,yy,xprime;
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@ -687,9 +737,11 @@ int main(int argc, char **argv) {
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mode13h_graphics_init();
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frame=0x13;
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// frame=0x13;
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es=0xa000-10;
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frame=2*512;
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while(1) {
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for(yy=0;yy<200;yy++) {
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for(xx=0;xx<320;xx++) {
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@ -698,7 +750,7 @@ int main(int argc, char **argv) {
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/* rrolla multiply by 0xcccd trick */
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which=frame/512;
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switch (which&0xff) {
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switch (which&0x7) {
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case 0: color=fx2(xx,yy,xprime); break;
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case 1: color=fx1(xx,yy,xprime); break;
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case 2: color=fx0(xx,yy,xprime); break;
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@ -706,7 +758,7 @@ int main(int argc, char **argv) {
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case 4: color=fx4(xx,yy,xprime); break;
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case 5: color=fx5(xx,yy,xprime); break;
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case 6: color=fx6(xx,yy,xprime); break;
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case 7: return 0;
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case 7: color=fx7(xx,yy,xprime); break;
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default: printf("Trying effect %d\n",which);
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}
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write_framebuffer((es<<4)+((yy*320)+xx), color);
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@ -8,14 +8,17 @@ B2D = ../bmp2dhr/b2d
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all: memories.dsk
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memories.dsk: HELLO CIRCLES.BAS CIRCLES CHECKERS CHECKERS_SMALL TUNNEL
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memories.dsk: HELLO CIRCLES.BAS CIRCLES CHECKERS CHECKERS_SMALL PLANE \
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TUNNEL TNM
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cp empty.dsk memories.dsk
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$(DOS33) -y memories.dsk SAVE A HELLO
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$(DOS33) -y memories.dsk SAVE A CIRCLES.BAS
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$(DOS33) -y memories.dsk BSAVE -a 0x070 CIRCLES
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$(DOS33) -y memories.dsk BSAVE -a 0x070 CHECKERS
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$(DOS33) -y memories.dsk BSAVE -a 0x070 CHECKERS_SMALL
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$(DOS33) -y memories.dsk BSAVE -a 0x1000 PLANE
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$(DOS33) -y memories.dsk BSAVE -a 0x1000 TUNNEL
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$(DOS33) -y memories.dsk BSAVE -a 0x1000 TNM
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CIRCLES: circles.o
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ld65 -o CIRCLES circles.o -C ../linker_scripts/apple2_70_zp.inc
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@ -33,12 +36,29 @@ checkers.o: checkers.s
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###
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PLANE: plane.o
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ld65 -o PLANE plane.o -C ../linker_scripts/apple2_1000.inc
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plane.o: plane.s
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ca65 -o plane.o plane.s -l plane.lst
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###
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TUNNEL: tunnel.o
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ld65 -o TUNNEL tunnel.o -C ../linker_scripts/apple2_1000.inc
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tunnel.o: tunnel.s
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ca65 -o tunnel.o tunnel.s -l tunnel.lst
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###
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TNM: tunnel_nm.o
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ld65 -o TNM tunnel_nm.o -C ../linker_scripts/apple2_1000.inc
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tunnel_nm.o: tunnel_nm.s
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ca65 -o tunnel_nm.o tunnel_nm.s -l tunnel_nm.lst
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###
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@ -62,5 +82,5 @@ CIRCLES.BAS: zooming_circles.bas
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clean:
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rm -f *~ *.o *.lst HELLO CIRCLES.BAS CIRCLES CHECKERS \
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CHECKERS_SMALL TUNNEL
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CHECKERS_SMALL PLANE TUNNEL TNM
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@ -0,0 +1,55 @@
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;=================================================
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; M1 * M2
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multiply_s8x8:
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stx TEMP ; save as we trash it
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lda M2
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eor M1 ; calc if we need to adjust at end
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; (++ vs +- vs -+ vs --)
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php ; save status on stack
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; if M1 negative, negate it
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lda M1
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bpl m1_positive
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eor #$ff
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clc
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adc #0
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m1_positive:
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sta M1
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; if M2 negative, naegate it
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lda M2
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bpl m2_positive
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eor #$ff
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clc
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adc #0
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m2_positive:
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sta M2
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;==================
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; unsigned multiply
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jsr multiply_u8x8
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; done, high result in factor2, low result in factor1
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; adjust to be signed
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; if m1 and m2 positive, good
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; if m1 and m2 negative, good
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; otherwise, negate result
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plp ; restore saved pos/neg value
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bpl done_result
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negate_result:
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sec
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lda #0
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sbc M1
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lda #0
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sbc M2
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done_result:
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sta M2
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ldx TEMP
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rts
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@ -0,0 +1,90 @@
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; Fast mutiply -- setup tables
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; Note for our purposes we only care about 8.8 x 8.8 fixed point
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; with 8.8 result, which means we only care about the middle two bytes
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; of the 32 bit result. So we disable generation of the high and low byte
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; to save some cycles.
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;
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; The old routine took around 700 cycles for a 16bitx16bit=32bit mutiply
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; This routine, at an expense of 2kB of looku tables, takes around 250
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; If you reuse a term the next time this drops closer to 200
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; This routine was described by Stephen Judd and found
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; in The Fridge and in the C=Hacking magazine
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; http://codebase64.org/doku.php?id=base:seriously_fast_multiplication
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; The key thing to note is that
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; (a+b)^2 (a-b)^2
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; a*b = ------- - --------
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; 4 4
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; So if you have tables of the squares of 0..511 you can lookup and subtract
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; instead of multiplying.
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; Table generation: I:0..511
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; square1_lo = <((I*I)/4)
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; square1_hi = >((I*I)/4)
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; square2_lo = <(((I-255)*(I-255))/4)
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; square2_hi = >(((I-255)*(I-255))/4)
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.ifndef square1_lo
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square1_lo = $2000
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square1_hi = $2200
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square2_lo = $2400
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square2_hi = $2600
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.endif
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; for(i=0;i<512;i++) {
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; square1_lo[i]=((i*i)/4)&0xff;
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; square1_hi[i]=(((i*i)/4)>>8)&0xff;
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; square2_lo[i]=( ((i-255)*(i-255))/4)&0xff;
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; square2_hi[i]=(( ((i-255)*(i-255))/4)>>8)&0xff;
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; }
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init_multiply_tables:
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; Build the add tables
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ldx #$00
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txa
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.byte $c9 ; CMP #immediate - skip TYA and clear carry flag
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lb1: tya
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adc #$00 ; 0
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ml1: sta square1_hi,x ; square1_hi[0]=0
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tay ; y=0
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cmp #$40 ; subtract 64 and update flags (c=0)
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txa ; a=0
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ror ; rotate
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ml9: adc #$00 ; add 0
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sta ml9+1 ; update add value
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inx ; x=1
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ml0: sta square1_lo,x ; square1_lo[0]=1
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bne lb1 ; if not zero, loop
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inc ml0+2 ; increment values
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inc ml1+2 ; increment values
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clc ; c=0
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iny ; y=1
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bne lb1 ; loop
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; Build the subtract tables based on the existing one
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ldx #$00
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ldy #$ff
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second_table:
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lda square1_hi+1,x
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sta square2_hi+$100,x
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lda square1_hi,x
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sta square2_hi,y
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lda square1_lo+1,x
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sta square2_lo+$100,x
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lda square1_lo,x
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sta square2_lo,y
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dey
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inx
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bne second_table
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rts
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@ -0,0 +1,56 @@
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; Fast mutiply
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; Note for our purposes we only care about 8.8 x 8.8 fixed point
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; with 8.8 result, which means we only care about the middle two bytes
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; of the 32 bit result. So we disable generation of the high and low byte
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; to save some cycles.
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;
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; The old routine took around 700 cycles for a 16bitx16bit=32bit mutiply
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; This routine, at an expense of 2kB of looku tables, takes around 250
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; If you reuse a term the next time this drops closer to 200
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; This routine was described by Stephen Judd and found
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; in The Fridge and in the C=Hacking magazine
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; http://codebase64.org/doku.php?id=base:seriously_fast_multiplication
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; The key thing to note is that
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; (a+b)^2 (a-b)^2
|
||||
; a*b = ------- - --------
|
||||
; 4 4
|
||||
; So if you have tables of the squares of 0..511 you can lookup and subtract
|
||||
; instead of multiplying.
|
||||
|
||||
; Table generation: I:0..511
|
||||
; square1_lo = <((I*I)/4)
|
||||
; square1_hi = >((I*I)/4)
|
||||
; square2_lo = <(((I-255)*(I-255))/4)
|
||||
; square2_hi = >(((I-255)*(I-255))/4)
|
||||
|
||||
|
||||
; Fast 8x8 bit unsigned multiplication, 16-bit result
|
||||
; Input: M1xM2
|
||||
; Result: M2:M1
|
||||
;
|
||||
multiply_u8x8:
|
||||
lda M1
|
||||
sta sm1a+1 ; 3
|
||||
sta sm3a+1 ; 3
|
||||
eor #$ff ; invert the bits for subtracting ; 2
|
||||
sta sm2a+1 ; 3
|
||||
sta sm4a+1 ; 3
|
||||
|
||||
ldx M2
|
||||
sec
|
||||
sm1a:
|
||||
lda square1_lo,X
|
||||
sm2a:
|
||||
sbc square2_lo,X
|
||||
sta M1
|
||||
sm3a:
|
||||
lda square1_hi,X
|
||||
sm4a:
|
||||
sbc square2_hi,X
|
||||
sta M2
|
||||
|
||||
rts
|
||||
|
|
@ -0,0 +1,128 @@
|
|||
; Tilted Plane, based on the code in Hellmood's Memories
|
||||
|
||||
; by deater (Vince Weaver) <vince@deater.net>
|
||||
|
||||
; Zero Page
|
||||
BASL = $28
|
||||
BASH = $29
|
||||
H2 = $2C
|
||||
COLOR = $30
|
||||
|
||||
X1 = $F0
|
||||
X2 = $F1
|
||||
Y1 = $F2
|
||||
Y2 = $F3
|
||||
|
||||
|
||||
M1 = $F7
|
||||
M2 = $F8
|
||||
|
||||
TEMP = $FA
|
||||
TEMPY = $FB
|
||||
FRAME = $FC
|
||||
TEMPX = $FD
|
||||
SCALED = $FE
|
||||
|
||||
|
||||
; Soft Switches
|
||||
KEYPRESS= $C000
|
||||
KEYRESET= $C010
|
||||
SET_GR = $C050 ; Enable graphics
|
||||
FULLGR = $C052 ; Full screen, no text
|
||||
PAGE0 = $C054 ; Page0
|
||||
PAGE1 = $C055 ; Page1
|
||||
LORES = $C056 ; Enable LORES graphics
|
||||
|
||||
; ROM routines
|
||||
|
||||
PLOT = $F800 ; plot, horiz=y, vert=A (A trashed, XY Saved)
|
||||
SETCOL = $F864
|
||||
TEXT = $FB36 ;; Set text mode
|
||||
BASCALC = $FBC1
|
||||
SETGR = $FB40
|
||||
HOME = $FC58 ;; Clear the text screen
|
||||
WAIT = $FCA8 ;; delay 1/2(26+27A+5A^2) us
|
||||
HLINE = $F819
|
||||
|
||||
tilted_plane:
|
||||
|
||||
|
||||
|
||||
;===================
|
||||
; init screen
|
||||
jsr SETGR ; 3
|
||||
bit FULLGR ; 3
|
||||
|
||||
jsr init_multiply_tables
|
||||
|
||||
plane_forever:
|
||||
|
||||
inc FRAME ; 2
|
||||
|
||||
ldx #47 ; yy ; 2
|
||||
yloop:
|
||||
ldy #39 ; xx ; 2
|
||||
xloop:
|
||||
|
||||
; clc
|
||||
; adc #$10 ; adjust top of screen
|
||||
lda division,X ; scaled=((0x3d5/yy)&0xff);
|
||||
; reverse divide AL=C/Y'
|
||||
|
||||
sta M1
|
||||
sta SCALED
|
||||
|
||||
; color=((signed char)((xprime-20)&0xff))*((signed char)(scaled&0xff));
|
||||
tya
|
||||
sec
|
||||
sbc #20
|
||||
sta M2
|
||||
|
||||
jsr multiply_s8x8
|
||||
|
||||
lda M1
|
||||
|
||||
rol
|
||||
rol M2
|
||||
rol
|
||||
rol M2
|
||||
|
||||
lda M2
|
||||
sta COLOR
|
||||
|
||||
; fedcba9876543210
|
||||
; dcba9876
|
||||
|
||||
|
||||
; color=(color>>6)&0xff;
|
||||
|
||||
sec
|
||||
lda SCALED
|
||||
sbc FRAME ; scaled-=frame;
|
||||
eor COLOR ; color^=(scaled&0xff);
|
||||
and #$1C ; color&=0x1c; // map colors
|
||||
|
||||
jsr SETCOL
|
||||
|
||||
txa ; A==Y1 ; 1
|
||||
jsr PLOT ; (X2,Y1) ; 3
|
||||
|
||||
dey ; 1
|
||||
bpl xloop ; 2
|
||||
|
||||
dex ; 1
|
||||
bpl yloop ; 2
|
||||
|
||||
bmi plane_forever ; 2
|
||||
|
||||
|
||||
division:
|
||||
.byte $62,$59,$51,$4B,$46,$41,$3D,$39,$36,$33
|
||||
.byte $31,$2E,$2C,$2A,$28,$27,$25,$24,$23,$21
|
||||
.byte $20,$1F,$1E,$1D,$1C,$1C,$1B,$1A,$19,$19
|
||||
.byte $18,$17,$17,$16,$16,$15,$15,$14,$14,$14
|
||||
.byte $13,$13,$12,$12,$12,$11,$11,$11
|
||||
|
||||
.include "multiply_tables.s"
|
||||
.include "multiply_s8x8.s"
|
||||
.include "multiply_u8x8.s"
|
||||
|
|
@ -2,6 +2,10 @@
|
|||
|
||||
; by deater (Vince Weaver) <vince@deater.net>
|
||||
|
||||
|
||||
; first try (shift/add multiply) = 160 bytes, 14 seconds/frame
|
||||
; second (lookup table mul) = 251 bytes, 9 seconds/frame
|
||||
|
||||
; Zero Page
|
||||
COLOR = $30
|
||||
|
||||
|
|
@ -32,6 +36,8 @@ tunnel:
|
|||
jsr SETGR ; 3
|
||||
bit FULLGR ; 3
|
||||
|
||||
jsr init_multiply_tables ; 3
|
||||
|
||||
tunnel_forever:
|
||||
|
||||
inc FRAME ; 2
|
||||
|
|
@ -71,8 +77,8 @@ fx5_loop:
|
|||
;sta M1 ; 2
|
||||
jsr imul ; 3
|
||||
|
||||
lda M2 ; 2
|
||||
sta VALUE ; 2
|
||||
; lda M2 ; 2
|
||||
sta VALUE ; high result in A ; 2
|
||||
|
||||
; get xcoord
|
||||
lda XCOORD ; 2
|
||||
|
|
@ -129,70 +135,15 @@ putpixel:
|
|||
; A = M1
|
||||
; DEPTH (preserve) is M2
|
||||
imul:
|
||||
stx TEMP ; save as we trash it
|
||||
|
||||
sta M1 ; get values in right place
|
||||
lda DEPTH
|
||||
sta M2
|
||||
|
||||
eor M1 ; calc if we need to adjust at end
|
||||
; (++ vs +- vs -+ vs --)
|
||||
php ; save status on stack
|
||||
jsr multiply_s8x8
|
||||
|
||||
; if M1 negative, negate it
|
||||
lda M1
|
||||
bpl m1_positive
|
||||
eor #$ff
|
||||
clc
|
||||
adc #0
|
||||
m1_positive:
|
||||
sta M1
|
||||
|
||||
; if M2 negative, naegate it
|
||||
lda M2
|
||||
bpl m2_positive
|
||||
eor #$ff
|
||||
clc
|
||||
adc #0
|
||||
m2_positive:
|
||||
sta M2
|
||||
|
||||
;==================
|
||||
; unsigned multiply
|
||||
|
||||
; factors in M1 and M2
|
||||
lda #0
|
||||
ldx #$8
|
||||
lsr M1
|
||||
clc
|
||||
imul_loop:
|
||||
bcc no_add
|
||||
clc
|
||||
adc M2
|
||||
no_add:
|
||||
ror
|
||||
ror M1
|
||||
dex
|
||||
bne imul_loop
|
||||
|
||||
sta M2
|
||||
; done, high result in factor2, low result in factor1
|
||||
|
||||
; adjust to be signed
|
||||
; if m1 and m2 positive, good
|
||||
; if m1 and m2 negative, good
|
||||
; otherwise, negate result
|
||||
|
||||
plp ; restore saved pos/neg value
|
||||
bpl done_result
|
||||
negate_result:
|
||||
sec
|
||||
lda #0
|
||||
sbc M1
|
||||
lda #0
|
||||
sbc M2
|
||||
done_result:
|
||||
sta M2
|
||||
|
||||
ldx TEMP
|
||||
rts
|
||||
|
||||
|
||||
.include "multiply_tables.s"
|
||||
.include "multiply_s8x8.s"
|
||||
.include "multiply_u8x8.s"
|
||||
|
|
|
|||
Loading…
Reference in New Issue