scrolling scrolling

1 files changed, 94 insertions, 29 deletions

diff --git a/main.c b/main.c
index 0aeb63d..fa0821d 100644
--- a/main.c
+++ b/main.c
@@ -11,9 +11,11 @@
 #include <sys/ioctl.h>
 #include <signal.h>
 #include <poll.h>
+#include <time.h>
 
 /* TODO
  *
+ * - one fwrite() per blit
  * - utf-8 input
  * - arrow keys
  * - KEY_RESIZE or draw callback
@@ -80,7 +82,10 @@ typedef struct {
 	unsigned width, height;
 	VuiBuffer buf1, buf2;
 	VuiBuffer *front, *back;
+	void (*redraw_fn)(void *ctx);
+	void *redraw_ctx;
 	int redraw_all;
+	int scroll_x, scroll_y;
 } VuiWindow;
 
 static struct termios vui_init_stdin_tos, vui_init_stdout_tos, vui_raw_stdin_tos, vui_raw_stdout_tos;
@@ -173,6 +178,13 @@ void vui_curs_vis(int vis) {
 	}
 }
 
+void vui_on_sigwinch(int _) {
+	vui_adjust();
+	if (vui_win.redraw_fn) {
+		vui_win.redraw_fn(vui_win.redraw_ctx);
+	}
+}
+
 void vui_init(void) {
 	tcgetattr(STDIN_FILENO, &vui_init_stdin_tos);
 	vui_raw_stdin_tos = vui_init_stdin_tos;
@@ -185,6 +197,7 @@ void vui_init(void) {
 	tcsetattr(STDOUT_FILENO, TCSANOW, &vui_raw_stdout_tos);
 
 	vui_adjust();
+	signal(SIGWINCH, vui_on_sigwinch);
 }
 
 
@@ -287,6 +300,9 @@ static void attr_chg(VuiAttr *ptr, VuiAttr to) {
 unsigned vui_changes = 0;
 unsigned vui_max_change = 0;
 unsigned vui_repainted = 0;
+
+void vui_scroll_buf(VuiBuffer *b, int dx, int dy);
+
 void vui_blit(void) {
 	VuiBuffer *front = vui_win.front;
 	VuiBuffer *back = vui_win.back;
@@ -311,6 +327,47 @@ void vui_blit(void) {
 	vui_max_change = 0;
 	vui_repainted = 0;
 	unsigned cur_x = 0, cur_y = 0;
+
+
+	/* TODO:
+	 *
+	 * Scroll without repainting whole screen:
+	 *
+	 * - \x1b[#L to insert blank lines
+	 * - \x1b[#@ to insert blank chars
+	 * - \x1b[#M to delete lines
+	 * - \x1b[#P to delete chars
+	 *
+	 */
+
+	if (vui_win.scroll_x || vui_win.scroll_y) {
+		if (vui_win.scroll_x < 0) {
+			for (unsigned y = 0; y < vui_win.height; y++) {
+				curs_move(cur_x, cur_y, 0, y);
+				printf("\x1b[%dP", -vui_win.scroll_x);
+				cur_y = y;
+			}
+		} else if (vui_win.scroll_x > 0) {
+			for (unsigned y = 0; y < vui_win.height; y++) {
+				curs_move(cur_x, cur_y, 0, y);
+				printf("\x1b[%d@", vui_win.scroll_x);
+				cur_y = y;
+			}
+		}
+		if (vui_win.scroll_y < 0) {
+			curs_move(cur_x, cur_y, 0, 0);
+			cur_x = (cur_y = 0);
+			printf("\x1b[%dM", -vui_win.scroll_y);
+		} else if (vui_win.scroll_y > 0) {
+			curs_move(cur_x, cur_y, 0, 0);
+			cur_x = (cur_y = 0);
+			printf("\x1b[%dL", vui_win.scroll_y);
+		}
+		vui_scroll_buf(back, vui_win.scroll_x, vui_win.scroll_y);
+		vui_win.scroll_x = 0;
+		vui_win.scroll_y = 0;
+	}
+
 	for (unsigned y = 0; y < vui_win.height; y++) {
 		unsigned x = 0;
 		while (x < vui_win.width) {
@@ -353,11 +410,13 @@ void vui_chr(int x, int y, char c) {
 }
 
 int vui_avprintf(int x, int y, VuiAttr a, const char *fmt, va_list ap) {
+	//return 0;
 	va_list ap2;
 	va_copy(ap2, ap);
 	int n = vsnprintf(NULL, 0, fmt, ap);
 	if (x < 0) x = vui_win.width + x - (n - 1);
 	if (y < 0) y = vui_win.height + y;
+	if (x >= vui_win.width || y >= vui_win.height) return n;
 	if (n > 0) {
 		char buf[n + 1];
 		vsnprintf(buf, n + 1, fmt, ap2);
@@ -385,11 +444,6 @@ int vui_printf(int x, int y, const char *fmt, ...) {
 	return r;
 }
 
-void on_sigwinch(int _) {
-	vui_adjust();
-	vui_blit();
-}
-
 int wait_for_input(int fd, int ms) {
 	return poll(&(struct pollfd) { .fd = fd, .events = POLLIN }, 1, ms);
 }
@@ -441,26 +495,46 @@ void vui_scroll_buf(VuiBuffer *b, int dx, int dy) {
 
 void vui_scroll(int dx, int dy) {
 	vui_scroll_buf(vui_win.front, dx, dy);
+	vui_win.scroll_x += dx;
+	vui_win.scroll_y += dy;
+}
+
+int x = 0, y = 0;
+int dx = 0, dy = 0;
+int camx = 0, camy = 0;
+int C = '*';
+unsigned frame = 0;
+int half_y = 1;
+
+void draw(void *ctx) {
+	(void)ctx;
+
+	vui_chra(x, y, C, ((x + y) & 0xf) | BG_BBLUE);
+	vui_chra(x-1, y, C, ((x + y) & 0xf) | BG_BLUE | A_UNDERSCORE);
+	vui_chra(x+1, y, C, ((x + y) & 0xf) | BG_BLUE | A_UNDERSCORE);
+	vui_chra(x, y-1, C, ((x + y) & 0xf) | BG_BLUE | A_UNDERSCORE);
+	vui_chra(x, y+1, C, ((x + y) & 0xf) | BG_BLUE | A_UNDERSCORE);
+
+	vui_printf(-1, -1, "(%u, %u)", vui_win.width, vui_win.height);
+	vui_printf(0, -1, "front buffer = %p", (void*)vui_win.front);
+	vui_printf(-1, 0, "longest change = %3u, changes = %5u, repainted%% = %02u%%, chars = %5u", vui_max_change, vui_changes, vui_repainted * 100 / (vui_win.width * vui_win.height), vui_win.width * vui_win.height);
+
+	vui_blit();
 }
 
 int main(int argc, const char **argv) {
 	vui_init();
 	vui_curs_vis(0);
-	signal(SIGWINCH, on_sigwinch);
-	int x = 0, y = 0;
-	int dx = 0, dy = 0;
-	int camx = 0, camy = 0;
-	int C = '*';
-	unsigned frame = 0;
-	int half_y = 0;
+
 	for (;;) {
 		frame++;
 		//camx += dx;
 		x += dx;
-		if ((frame & 1) || !(half_y)) {
-			// camy += dy;
-			y += dy;
+		int ydy = dy;
+		if (half_y) {
+			ydy = (frame & 1) ? (dy / 2) : dy - (dy / 2);
 		}
+		y += ydy;
 
 		unsigned left = 32;
 		unsigned right = vui_win.width - (left + 1);
@@ -484,8 +558,9 @@ int main(int argc, const char **argv) {
 		*/
 
 		static int paused = 0;
+		vui_win.redraw_fn = draw;
 
-#if 1
+#if 0
 		/* weird cellular automata */
 		if (!paused) {
 			// int dx = 0, dy = 0; /* shadow on purpose */
@@ -532,21 +607,11 @@ int main(int argc, const char **argv) {
 			}
 		}
 #endif
-
-		vui_chra(x, y, C, ((x + y) & 0xf) | BG_BBLUE);
-		vui_chra(x-1, y, C, ((x + y) & 0xf) | BG_BLUE | A_UNDERSCORE);
-		vui_chra(x+1, y, C, ((x + y) & 0xf) | BG_BLUE | A_UNDERSCORE);
-		vui_chra(x, y-1, C, ((x + y) & 0xf) | BG_BLUE | A_UNDERSCORE);
-		vui_chra(x, y+1, C, ((x + y) & 0xf) | BG_BLUE | A_UNDERSCORE);
-
-		vui_printf(-1, -1, "(%u, %u)", vui_win.width, vui_win.height);
-		vui_printf(0, -1, "front buffer = %p", (void*)vui_win.front);
-		vui_printf(-1, 0, "longest change = %3u, changes = %5u, repainted%% = %02u%%, chars = %5u", vui_max_change, vui_changes, vui_repainted * 100 / (vui_win.width * vui_win.height), vui_win.width * vui_win.height);
-
 		// win.redraw_all = 1;
-		vui_blit();
+		draw(NULL);
 
-		if (!wait_for_input(STDIN_FILENO, 20)) continue;
+		clock_nanosleep(CLOCK_MONOTONIC, 0, &(struct timespec) { .tv_nsec = 15 * 1000000 }, NULL);
+		if (!wait_for_input(STDIN_FILENO, 0)) continue;
 		int c = getchar();
 
 		if (c == 'q') break;