---
 left.c | 14 ++++++++++++++
 1 file changed, 14 insertions(+)

diff --git a/left.c b/left.c
index 1959854..6559922 100644
--- a/left.c
+++ b/left.c
@@ -649,6 +649,13 @@ domouse(SDL_Event *event)
 	}
 }
 
+void doresize(int n)
+{
+	ZOOM = clamp(ZOOM+n,1,8);
+	SDL_SetWindowSize(gWindow, WIDTH*ZOOM, HEIGHT*ZOOM);
+	redraw(pixels);
+}
+
 void
 dokey(SDL_Event *event)
 {
@@ -693,6 +700,13 @@ dokey(SDL_Event *event)
 		if(ctrl)
 			savetxt();
 		break;
+	case SDLK_PLUS:
+	case SDLK_EQUALS:
+		if(ctrl)doresize(1);
+		break;
+	case SDLK_MINUS:
+		if(ctrl)doresize(-1);
+		break;
 	}
 }
 
-- 
2.29.2

---
 left.c | 13 +++++++------
 1 file changed, 7 insertions(+), 6 deletions(-)

diff --git a/left.c b/left.c
index 6559922..0903680 100644
--- a/left.c
+++ b/left.c
@@ -34,7 +34,8 @@ typedef struct {
 
 int WIDTH = 8 * HOR + 8 * PAD * 2;
 int HEIGHT = 8 * (VER + 2) + 8 * PAD * 2;
-int FPS = 30, GUIDES = 1, ZOOM = 1, DOWN = 0;
+int FPS = 30, GUIDES = 1, DOWN = 0;
+float ZOOM = 1;
 int RULER = 60;
 
 /* interface */
@@ -649,9 +650,9 @@ domouse(SDL_Event *event)
 	}
 }
 
-void doresize(int n)
+void doresize(float n)
 {
-	ZOOM = clamp(ZOOM+n,1,8);
+	ZOOM = (ZOOM+n < 0.5) ? 0.5 : (ZOOM+n > 8) ? 8 : ZOOM+n;
 	SDL_SetWindowSize(gWindow, WIDTH*ZOOM, HEIGHT*ZOOM);
 	redraw(pixels);
 }
@@ -702,10 +703,10 @@ dokey(SDL_Event *event)
 		break;
 	case SDLK_PLUS:
 	case SDLK_EQUALS:
-		if(ctrl)doresize(1);
+		if(ctrl)doresize(0.5);
 		break;
 	case SDLK_MINUS:
-		if(ctrl)doresize(-1);
+		if(ctrl)doresize(-0.5);
 		break;
 	}
 }
@@ -750,7 +751,7 @@ init(void)
 		SDL_WINDOWPOS_UNDEFINED,
 		WIDTH * ZOOM,
 		HEIGHT * ZOOM,
-		SDL_WINDOW_SHOWN);
+		SDL_WINDOW_SHOWN | SDL_WINDOW_ALLOW_HIGHDPI);
 	if(gWindow == NULL)
 		return error("Window", SDL_GetError());
 	gRenderer = SDL_CreateRenderer(gWindow, -1, 0);
-- 
2.29.2