ref: a0f376efbd50f16694d4c533d4b2836cfbd48d2c
parent: 3dc0fce9b8f7ef2a900a9f27d72c6c7accc4e4c0
author: Simon Tatham <anakin@pobox.com>
date: Thu May 26 13:03:51 EDT 2005
Sorted out the barriers/corners trouble left by r5844. No wonder Jacob wasn't able to find a satisfactory fix: the whole area was a horrid mess. Fortunately, the reason it was a horrid mess was because the Net drawing routines predated the introduction of clip() in the frontend interface, and it turns out that clip() makes it possible to do all this more easily and better. So, a complete rearchitecting of barrier corners: the corner flags in the `barriers' array are now gone (and good riddance), and corner information is computed on the fly so as to take into account the moving grid edges. In the process I've also updated the corner mechanism so that a barrier `corner' (really endpoint) is drawn at the end of _every_ barrier, not just where two meet. This has changed the appearance of a single isolated barrier, to what I would have wanted it to look like in the first place but achieving it without clip() was just too fiddly. [originally from svn r5846] [r5844 == 865e8ad6ca3d83ad2a585ceeb1809e9f68c18a20]
--- a/net.c
+++ b/net.c
@@ -28,11 +28,6 @@
#define D 0x08
#define LOCKED 0x10
#define ACTIVE 0x20
-/* Corner flags go in the barriers array */
-#define RU 0x10
-#define UL 0x20
-#define LD 0x40
-#define DR 0x80
/* Rotations: Anticlockwise, Clockwise, Flip, general rotate */
#define A(x) ( (((x) & 0x07) << 1) | (((x) & 0x08) >> 3) )
@@ -1646,44 +1641,6 @@
state->wrapping = TRUE;
}
- /*
- * Set up the barrier corner flags, for drawing barriers
- * prettily when they meet.
- */
- for (y = 0; y < state->height; y++) {- for (x = 0; x < state->width; x++) {- int dir;
-
- for (dir = 1; dir < 0x10; dir <<= 1) {- int dir2 = A(dir);
- int x1, y1, x2, y2, x3, y3;
- int corner = FALSE;
-
- if (!(barrier(state, x, y) & dir))
- continue;
-
- if (barrier(state, x, y) & dir2)
- corner = TRUE;
-
- OFFSET(x1, y1, x, y, dir, state);
- if (barrier(state, x1, y1) & dir2)
- corner = TRUE;
-
- OFFSET(x2, y2, x, y, dir2, state);
- if (barrier(state, x2, y2) & dir)
- corner = TRUE;
-
- if (corner) {- barrier(state, x, y) |= (dir << 4);
- barrier(state, x1, y1) |= (A(dir) << 4);
- barrier(state, x2, y2) |= (C(dir) << 4);
- OFFSET(x3, y3, x1, y1, dir2, state);
- barrier(state, x3, y3) |= (F(dir) << 4);
- }
- }
- }
- }
-
return state;
}
@@ -2136,37 +2093,31 @@
/*
* draw_barrier_corner() and draw_barrier() are passed physical coords
*/
-static void draw_barrier_corner(frontend *fe, int x, int y, int dir, int phase,
- int barrier)
+static void draw_barrier_corner(frontend *fe, int x, int y, int dx, int dy,
+ int phase)
{int bx = WINDOW_OFFSET + TILE_SIZE * x;
int by = WINDOW_OFFSET + TILE_SIZE * y;
- int x1, y1, dx, dy, dir2;
+ int x1, y1;
- dir >>= 4;
-
- dir2 = A(dir);
- dx = X(dir) + X(dir2);
- dy = Y(dir) + Y(dir2);
x1 = (dx > 0 ? TILE_SIZE+TILE_BORDER-1 : 0);
y1 = (dy > 0 ? TILE_SIZE+TILE_BORDER-1 : 0);
if (phase == 0) {- draw_rect_coords(fe, bx+x1, by+y1,
+ draw_rect_coords(fe, bx+x1+dx, by+y1,
bx+x1-TILE_BORDER*dx, by+y1-(TILE_BORDER-1)*dy,
- barrier ? COL_WIRE : COL_BACKGROUND);
- draw_rect_coords(fe, bx+x1, by+y1,
+ COL_WIRE);
+ draw_rect_coords(fe, bx+x1, by+y1+dy,
bx+x1-(TILE_BORDER-1)*dx, by+y1-TILE_BORDER*dy,
- barrier ? COL_WIRE : COL_BACKGROUND);
+ COL_WIRE);
} else {draw_rect_coords(fe, bx+x1, by+y1,
bx+x1-(TILE_BORDER-1)*dx, by+y1-(TILE_BORDER-1)*dy,
- barrier ? COL_BARRIER : COL_BORDER);
+ COL_BARRIER);
}
}
-static void draw_barrier(frontend *fe, int x, int y, int dir, int phase,
- int barrier)
+static void draw_barrier(frontend *fe, int x, int y, int dir, int phase)
{int bx = WINDOW_OFFSET + TILE_SIZE * x;
int by = WINDOW_OFFSET + TILE_SIZE * y;
@@ -2178,11 +2129,9 @@
h = (Y(dir) ? TILE_BORDER : TILE_SIZE - TILE_BORDER);
if (phase == 0) {- draw_rect(fe, bx+x1-X(dir), by+y1-Y(dir), w, h,
- barrier ? COL_WIRE : COL_BACKGROUND);
+ draw_rect(fe, bx+x1-X(dir), by+y1-Y(dir), w, h, COL_WIRE);
} else {- draw_rect(fe, bx+x1, by+y1, w, h,
- barrier ? COL_BARRIER : COL_BORDER);
+ draw_rect(fe, bx+x1, by+y1, w, h, COL_BARRIER);
}
}
@@ -2203,17 +2152,10 @@
* and including the borders around the tile. This means that
* if the neighbouring tiles have connections to those borders,
* we must draw those connections on the borders themselves.
- *
- * This would be terribly fiddly if we ever had to draw a tile
- * while its neighbour was in mid-rotate, because we'd have to
- * arrange to _know_ that the neighbour was being rotated and
- * hence had an anomalous effect on the redraw of this tile.
- * Fortunately, the drawing algorithm avoids ever calling us in
- * this circumstance: we're either drawing lots of straight
- * tiles at game start or after a move is complete, or we're
- * repeatedly drawing only the rotating tile. So no problem.
*/
+ clip(fe, bx, by, TILE_SIZE+TILE_BORDER, TILE_SIZE+TILE_BORDER);
+
/*
* So. First blank the tile out completely: draw a big
* rectangle in border colour, and a smaller rectangle in
@@ -2361,14 +2303,55 @@
* Draw barrier corners, and then barriers.
*/
for (phase = 0; phase < 2; phase++) {+ for (dir = 1; dir < 0x10; dir <<= 1) {+ int x1, y1, corner = FALSE;
+ /*
+ * If at least one barrier terminates at the corner
+ * between dir and A(dir), draw a barrier corner.
+ */
+ if (barrier(state, GX(x), GY(y)) & (dir | A(dir))) {+ corner = TRUE;
+ } else {+ /*
+ * Only count barriers terminating at this corner
+ * if they're physically next to the corner. (That
+ * is, if they've wrapped round from the far side
+ * of the screen, they don't count.)
+ */
+ x1 = x + X(dir);
+ y1 = y + Y(dir);
+ if (x1 >= 0 && x1 < state->width &&
+ y1 >= 0 && y1 < state->height &&
+ (barrier(state, GX(x1), GY(y1)) & A(dir))) {+ corner = TRUE;
+ } else {+ x1 = x + X(A(dir));
+ y1 = y + Y(A(dir));
+ if (x1 >= 0 && x1 < state->width &&
+ y1 >= 0 && y1 < state->height &&
+ (barrier(state, GX(x1), GY(y1)) & dir))
+ corner = TRUE;
+ }
+ }
+
+ if (corner) {+ /*
+ * At least one barrier terminates here. Draw a
+ * corner.
+ */
+ draw_barrier_corner(fe, x, y,
+ X(dir)+X(A(dir)), Y(dir)+Y(A(dir)),
+ phase);
+ }
+ }
+
for (dir = 1; dir < 0x10; dir <<= 1)
- if (barrier(state, GX(x), GY(y)) & (dir << 4))
- draw_barrier_corner(fe, x, y, dir << 4, phase, TRUE);
- for (dir = 1; dir < 0x10; dir <<= 1)
if (barrier(state, GX(x), GY(y)) & dir)
- draw_barrier(fe, x, y, dir, phase, TRUE);
+ draw_barrier(fe, x, y, dir, phase);
}
+ unclip(fe);
+
draw_update(fe, bx, by, TILE_SIZE+TILE_BORDER, TILE_SIZE+TILE_BORDER);
}
@@ -2380,9 +2363,12 @@
float angle = 0.0;
/*
- * Clear the screen if this is our first call.
+ * Clear the screen, and draw the exterior barrier lines, if
+ * this is our first call or if the origin has changed.
*/
- if (!ds->started) {+ if (!ds->started || ui->org_x != ds->org_x || ui->org_y != ds->org_y) {+ int phase;
+
ds->started = TRUE;
draw_rect(fe, 0, 0,
@@ -2390,15 +2376,6 @@
WINDOW_OFFSET * 2 + TILE_SIZE * state->height + TILE_BORDER,
COL_BACKGROUND);
- }
-
- /*
- * If the origin has changed, we need to redraw the exterior
- * barrier lines.
- */
- if (ui->org_x != ds->org_x || ui->org_y != ds->org_y) {- int phase;
-
ds->org_x = ui->org_x;
ds->org_y = ui->org_y;
moved_origin = TRUE;
@@ -2406,29 +2383,45 @@
draw_update(fe, 0, 0,
WINDOW_OFFSET*2 + TILE_SIZE*state->width + TILE_BORDER,
WINDOW_OFFSET*2 + TILE_SIZE*state->height + TILE_BORDER);
-
+
for (phase = 0; phase < 2; phase++) { for (x = 0; x < ds->width; x++) {- int ub = barrier(state, GX(x), GY(0));
- int db = barrier(state, GX(x), GY(ds->height-1));
- draw_barrier_corner(fe, x, -1, LD, phase, ub & UL);
- draw_barrier_corner(fe, x, -1, DR, phase, ub & RU);
- draw_barrier(fe, x, -1, D, phase, ub & U);
- draw_barrier_corner(fe, x, ds->height, RU, phase, db & DR);
- draw_barrier_corner(fe, x, ds->height, UL, phase, db & LD);
- draw_barrier(fe, x, ds->height, U, phase, db & D);
+ if (x+1 < ds->width) {+ if (barrier(state, GX(x), GY(0)) & R)
+ draw_barrier_corner(fe, x, -1, +1, +1, phase);
+ if (barrier(state, GX(x), GY(ds->height-1)) & R)
+ draw_barrier_corner(fe, x, ds->height, +1, -1, phase);
+ }
+ if (barrier(state, GX(x), GY(0)) & U) {+ draw_barrier_corner(fe, x, -1, -1, +1, phase);
+ draw_barrier_corner(fe, x, -1, +1, +1, phase);
+ draw_barrier(fe, x, -1, D, phase);
+ }
+ if (barrier(state, GX(x), GY(ds->height-1)) & D) {+ draw_barrier_corner(fe, x, ds->height, -1, -1, phase);
+ draw_barrier_corner(fe, x, ds->height, +1, -1, phase);
+ draw_barrier(fe, x, ds->height, U, phase);
+ }
}
for (y = 0; y < ds->height; y++) {- int lb = barrier(state, GX(0), GY(y));
- int rb = barrier(state, GX(ds->width-1), GY(y));
- draw_barrier_corner(fe, -1, y, RU, phase, lb & UL);
- draw_barrier_corner(fe, -1, y, DR, phase, lb & LD);
- draw_barrier(fe, -1, y, R, phase, lb & L);
- draw_barrier_corner(fe, ds->width, y, UL, phase, rb & RU);
- draw_barrier_corner(fe, ds->width, y, LD, phase, rb & DR);
- draw_barrier(fe, ds->width, y, L, phase, rb & R);
+ if (y+1 < ds->height) {+ if (barrier(state, GX(0), GY(y)) & D)
+ draw_barrier_corner(fe, -1, y, +1, +1, phase);
+ if (barrier(state, GX(ds->width-1), GY(y)) & D)
+ draw_barrier_corner(fe, ds->width, y, -1, +1, phase);
+ }
+ if (barrier(state, GX(0), GY(y)) & L) {+ draw_barrier_corner(fe, -1, y, +1, -1, phase);
+ draw_barrier_corner(fe, -1, y, +1, +1, phase);
+ draw_barrier(fe, -1, y, R, phase);
+ }
+ if (barrier(state, GX(ds->width-1), GY(y)) & R) {+ draw_barrier_corner(fe, ds->width, y, -1, -1, phase);
+ draw_barrier_corner(fe, ds->width, y, -1, +1, phase);
+ draw_barrier(fe, ds->width, y, L, phase);
+ }
}
}
}