Updating

1 files changed, 141 insertions, 0 deletions

diff --git a/src/air.c b/src/air.c
new file mode 100644
index 0000000..dd98a12
--- /dev/null
+++ b/src/air.c
@@ -0,0 +1,141 @@
+#include <math.h>
+#include <air.h>
+#include <powder.h>
+#include <defines.h>
+float kernel[9];
+
+float vx[YRES/CELL][XRES/CELL], ovx[YRES/CELL][XRES/CELL];
+float vy[YRES/CELL][XRES/CELL], ovy[YRES/CELL][XRES/CELL];
+float pv[YRES/CELL][XRES/CELL], opv[YRES/CELL][XRES/CELL];
+
+float cb_vx[YRES/CELL][XRES/CELL], cb_ovx[YRES/CELL][XRES/CELL];
+float cb_vy[YRES/CELL][XRES/CELL], cb_ovy[YRES/CELL][XRES/CELL];
+float cb_pv[YRES/CELL][XRES/CELL], cb_opv[YRES/CELL][XRES/CELL];
+
+float fvx[YRES/CELL][XRES/CELL], fvy[YRES/CELL][XRES/CELL];
+
+void make_kernel(void)
+{
+    int i, j;
+    float s = 0.0f;
+    for(j=-1; j<2; j++)
+        for(i=-1; i<2; i++)
+        {
+            kernel[(i+1)+3*(j+1)] = expf(-2.0f*(i*i+j*j));
+            s += kernel[(i+1)+3*(j+1)];
+        }
+    s = 1.0f / s;
+    for(j=-1; j<2; j++)
+        for(i=-1; i<2; i++)
+            kernel[(i+1)+3*(j+1)] *= s;
+}
+void update_air(void)
+{
+    int x, y, i, j;
+    float dp, dx, dy, f, tx, ty;
+
+    for(y=1; y<YRES/CELL; y++)
+        for(x=1; x<XRES/CELL; x++)
+        {
+            dp = 0.0f;
+            dp += vx[y][x-1] - vx[y][x];
+            dp += vy[y-1][x] - vy[y][x];
+            pv[y][x] *= PLOSS;
+            pv[y][x] += dp*TSTEPP;
+        }
+
+    for(y=0; y<YRES/CELL-1; y++)
+        for(x=0; x<XRES/CELL-1; x++)
+        {
+            dx = dy = 0.0f;
+            dx += pv[y][x] - pv[y][x+1];
+            dy += pv[y][x] - pv[y+1][x];
+            vx[y][x] *= VLOSS;
+            vy[y][x] *= VLOSS;
+            vx[y][x] += dx*TSTEPV;
+            vy[y][x] += dy*TSTEPV;
+            if(bmap[y][x]==1 || bmap[y][x+1]==1 ||
+                    bmap[y][x]==8 || bmap[y][x+1]==8 ||
+                    (bmap[y][x]==7 && !emap[y][x]) ||
+                    (bmap[y][x+1]==7 && !emap[y][x+1]))
+                vx[y][x] = 0;
+            if(bmap[y][x]==1 || bmap[y+1][x]==1 ||
+                    bmap[y][x]==8 || bmap[y+1][x]==8 ||
+                    (bmap[y][x]==7 && !emap[y][x]) ||
+                    (bmap[y+1][x]==7 && !emap[y+1][x]))
+                vy[y][x] = 0;
+        }
+
+    for(y=0; y<YRES/CELL; y++)
+        for(x=0; x<XRES/CELL; x++)
+        {
+            dx = 0.0f;
+            dy = 0.0f;
+            dp = 0.0f;
+            for(j=-1; j<2; j++)
+                for(i=-1; i<2; i++)
+                    if(y+j>0 && y+j<YRES/CELL-1 &&
+                            x+i>0 && x+i<XRES/CELL-1 &&
+                            bmap[y+j][x+i]!=1 &&
+                            bmap[y+j][x+i]!=8 &&
+                            (bmap[y+j][x+i]!=7 || emap[y+j][x+i]))
+                    {
+                        f = kernel[i+1+(j+1)*3];
+                        dx += vx[y+j][x+i]*f;
+                        dy += vy[y+j][x+i]*f;
+                        dp += pv[y+j][x+i]*f;
+                    }
+                    else
+                    {
+                        f = kernel[i+1+(j+1)*3];
+                        dx += vx[y][x]*f;
+                        dy += vy[y][x]*f;
+                        dp += pv[y][x]*f;
+                    }
+
+            tx = x - dx*0.7f;
+            ty = y - dy*0.7f;
+            i = (int)tx;
+            j = (int)ty;
+            tx -= i;
+            ty -= j;
+            if(i>=2 && i<XRES/CELL-3 &&
+                    j>=2 && j<YRES/CELL-3)
+            {
+                dx *= 1.0f - VADV;
+                dy *= 1.0f - VADV;
+
+                dx += VADV*(1.0f-tx)*(1.0f-ty)*vx[j][i];
+                dy += VADV*(1.0f-tx)*(1.0f-ty)*vy[j][i];
+
+                dx += VADV*tx*(1.0f-ty)*vx[j][i+1];
+                dy += VADV*tx*(1.0f-ty)*vy[j][i+1];
+
+                dx += VADV*(1.0f-tx)*ty*vx[j+1][i];
+                dy += VADV*(1.0f-tx)*ty*vy[j+1][i];
+
+                dx += VADV*tx*ty*vx[j+1][i+1];
+                dy += VADV*tx*ty*vy[j+1][i+1];
+            }
+
+            if(bmap[y][x] == 4)
+            {
+                dx += fvx[y][x];
+                dy += fvy[y][x];
+            }
+
+            if(dp > 256.0f) dp = 256.0f;
+            if(dp < -256.0f) dp = -256.0f;
+            if(dx > 256.0f) dx = 256.0f;
+            if(dx < -256.0f) dx = -256.0f;
+            if(dy > 256.0f) dy = 256.0f;
+            if(dy < -256.0f) dy = -256.0f;
+
+            ovx[y][x] = dx;
+            ovy[y][x] = dy;
+            opv[y][x] = dp;
+        }
+    memcpy(vx, ovx, sizeof(vx));
+    memcpy(vy, ovy, sizeof(vy));
+    memcpy(pv, opv, sizeof(pv));
+}