looks right, extremely slow

[gbajam22] / src / voxscape.c

diff --git a/src/voxscape.c b/src/voxscape.c
index 462ed75..ef11974 100644 (file)
--- a/src/voxscape.c
+++ b/src/voxscape.c
@@ -7,6 +7,9 @@
 #include "voxscape.h"
 #include "debug.h"
 
+#define FBWIDTH                240
+#define FBHEIGHT       160
+
 #define XLERP(a, b, t, fp) \
        ((((a) << (fp)) + ((b) - (a)) * (t)) >> fp)
 
@@ -226,7 +229,8 @@ void vox_begin(struct voxscape *vox)
 {
        int i;
 
-       memset(vox->coltop, 0, vox->fbwidth * sizeof *vox->coltop);
+       memset(vox->fb, 0, FBWIDTH * FBHEIGHT);
+       memset(vox->coltop, 0, FBWIDTH * sizeof *vox->coltop);
 
        if(!(vox->valid & SLICELEN)) {
                float theta = (float)vox->fov * M_PI / 360.0f;  /* half angle */
@@ -239,7 +243,7 @@ void vox_begin(struct voxscape *vox)
 
 void vox_render_slice(struct voxscape *vox, int n)
 {
-       int i, j, hval, colstart, colheight, z;
+       int i, j, hval, colstart, colheight, col, z;
        int32_t x, y, len, xstep, ystep;
        uint8_t color;
        uint16_t *fbptr;
@@ -247,29 +251,48 @@ void vox_render_slice(struct voxscape *vox, int n)
        z = vox->znear + n;
 
        len = vox->slicelen[n] >> 8;
-       xstep = ((COS(vox->angle) >> 8) * len) / vox->fbwidth;
-       ystep = ((SIN(vox->angle) >> 8) * len) / vox->fbwidth;
+       xstep = (((COS(vox->angle) >> 4) * len) >> 4) / FBWIDTH;
+       ystep = (((SIN(vox->angle) >> 4) * len) >> 4) / FBWIDTH;
+
+       x = vox->x - SIN(vox->angle) * z - xstep * (FBWIDTH / 2);
+       y = vox->y + COS(vox->angle) * z - ystep * (FBWIDTH / 2);
 
-       x = vox->x - SIN(vox->angle) * z - xstep * (vox->fbwidth >> 1);
-       y = vox->y + COS(vox->angle) * z - ystep * (vox->fbwidth >> 1);
-       /* TODO double column */
-       for(i=0; i<vox->fbwidth/2; i++) {
+       for(i=0; i<FBWIDTH / 2; i++) {
+               col = i * 2;
                hval = vox_height(vox, x, y) - vox->vheight;
-               hval = hval * 160 / (vox->znear + n) + vox->horizon;
-               if(hval > vox->fbheight) hval = vox->fbheight;
-               if(hval > vox->coltop[i]) {
+               hval = hval * 40 / (vox->znear + n) + vox->horizon;
+               if(hval > FBHEIGHT) hval = FBHEIGHT;
+               if(hval > vox->coltop[col]) {
                        color = vox_color(vox, x, y);
-                       colstart = vox->fbheight - hval;
-                       colheight = hval - vox->coltop[i];
-                       fbptr = vox->fb + colstart * vox->fbwidth / 2 + i / 2;
+                       colstart = FBHEIGHT - hval;
+                       colheight = hval - vox->coltop[col];
+                       fbptr = vox->fb + colstart * (FBWIDTH / 2) + i;
 
                        for(j=0; j<colheight; j++) {
-                               *fbptr = color | ((uint16_t)color << 8);
-                               fbptr += vox->fbwidth >> 1;
+                               *fbptr |= color;
+                               fbptr += FBWIDTH / 2;
                        }
-                       vox->coltop[i] = hval;
+                       vox->coltop[col] = hval;
                }
+               x += xstep;
+               y += ystep;
 
+               col++;
+               hval = vox_height(vox, x, y) - vox->vheight;
+               hval = hval * 40 / (vox->znear + n) + vox->horizon;
+               if(hval > FBHEIGHT) hval = FBHEIGHT;
+               if(hval > vox->coltop[col]) {
+                       color = vox_color(vox, x, y);
+                       colstart = FBHEIGHT - hval;
+                       colheight = hval - vox->coltop[col];
+                       fbptr = vox->fb + colstart * (FBWIDTH / 2) + i;
+
+                       for(j=0; j<colheight; j++) {
+                               *fbptr |= ((uint16_t)color << 8);
+                               fbptr += FBWIDTH / 2;
+                       }
+                       vox->coltop[col] = hval;
+               }
                x += xstep;
                y += ystep;
        }
@@ -277,44 +300,70 @@ void vox_render_slice(struct voxscape *vox, int n)
 
 void vox_sky_solid(struct voxscape *vox, uint8_t color)
 {
-       int i, j, colheight;
+       int i, j, colh0, colh1, colhboth;
        uint16_t *fbptr;
 
-       /* TODO double columns */
-       for(i=0; i<vox->fbwidth/2; i++) {
+       for(i=0; i<FBWIDTH / 2; i++) {
                fbptr = vox->fb + i;
-               colheight = vox->fbheight - vox->coltop[i];
-               for(j=0; j<colheight; j++) {
+               colh0 = FBHEIGHT - vox->coltop[i << 1];
+               colh1 = FBHEIGHT - vox->coltop[(i << 1) + 1];
+               colhboth = colh0 < colh1 ? colh0 : colh1;
+
+               for(j=0; j<colhboth; j++) {
                        *fbptr = color | ((uint16_t)color << 8);
-                       fbptr += vox->fbwidth >> 1;
+                       fbptr += FBWIDTH / 2;
+               }
+
+               if(colh0 > colh1) {
+                       for(j=colhboth; j<colh0; j++) {
+                               *fbptr |= color;
+                               fbptr += FBWIDTH / 2;
+                       }
+               } else {
+                       for(j=colhboth; j<colh1; j++) {
+                               *fbptr |= (uint16_t)color << 8;
+                               fbptr += FBWIDTH / 2;
+                       }
                }
        }
 }
 
 void vox_sky_grad(struct voxscape *vox, uint8_t chor, uint8_t ctop)
 {
-       int i, j, colheight, t;
-       int d = vox->fbheight - vox->horizon;
-       uint8_t *grad;
+       int i, j, colh0, colh1, colhboth, t;
+       int d = FBHEIGHT - vox->horizon;
+       uint8_t grad[FBHEIGHT];
        uint16_t *fbptr;
 
-       grad = alloca(vox->fbheight * sizeof *grad);
-
        for(i=0; i<d; i++) {
-               t = (i << 8) / d;
-               grad[i] = XLERP(ctop, chor, t, 8);
+               t = (i << 16) / d;
+               grad[i] = XLERP(ctop, chor, t, 16);
        }
-       for(i=d; i<vox->fbheight; i++) {
+       for(i=d; i<FBHEIGHT; i++) {
                grad[i] = chor;
        }
 
-       /* TODO double columns */
-       for(i=0; i<vox->fbwidth/2; i++) {
-               fbptr = vox->fb + i / 2;
-               colheight = vox->fbheight - vox->coltop[i];
-               for(j=0; j<colheight; j++) {
+       for(i=0; i<FBWIDTH / 2; i++) {
+               fbptr = vox->fb + i;
+               colh0 = FBHEIGHT - vox->coltop[i << 1];
+               colh1 = FBHEIGHT - vox->coltop[(i << 1) + 1];
+               colhboth = colh0 < colh1 ? colh0 : colh1;
+
+               for(j=0; j<colhboth; j++) {
                        *fbptr = grad[j] | ((uint16_t)grad[j] << 8);
-                       fbptr += vox->fbwidth >> 1;
+                       fbptr += FBWIDTH / 2;
+               }
+
+               if(colh0 > colh1) {
+                       for(j=colhboth; j<colh0; j++) {
+                               *fbptr |= grad[j];
+                               fbptr += FBWIDTH / 2;
+                       }
+               } else {
+                       for(j=colhboth; j<colh1; j++) {
+                               *fbptr |= (uint16_t)grad[j] << 8;
+                               fbptr += FBWIDTH / 2;
+                       }
                }
        }
 }