From 4a32e355a03254c04b5a2af3cb49db40609f8412 Mon Sep 17 00:00:00 2001
From: hgn <hgodden00@gmail.com>
Date: Mon, 10 Jan 2022 15:53:57 +0000
Subject: [PATCH] zoom revision

---
 fishladder.c | 100 ++++++++++++++++++---------------------------------
 1 file changed, 34 insertions(+), 66 deletions(-)

diff --git a/fishladder.c b/fishladder.c
index bb3c98a..c3f83a7 100644
--- a/fishladder.c
+++ b/fishladder.c
@@ -1510,81 +1510,49 @@ static void vg_update(void)
 	world.tile_y = floorf( world.tile_pos[1] );
 
 	// Camera dragging
-	static v2f drag_origin; // x/y pixel
-
-	if( vg_get_button_down( "tertiary" ) )
-		v2_copy( vg_mouse, drag_origin );
-	else if( vg_get_button( "tertiary" ) )
-	{
-		// get offset
-		v2_sub( vg_mouse, drag_origin, drag_offset );
-		v2_div( drag_offset, (v2f){ vg_window_x, vg_window_y }, drag_offset );
-		v2_mul( drag_offset, (v2f){ size_current*2.0f, -size_current*r1*2.0f }, drag_offset );
-	}
-	else
 	{
-		v2_copy( result_view, view_point );
-		v2_copy( (v2f){0.0f,0.0f}, drag_offset );
-	}
-
-	// calculate relative position of mouse in view_point space
-	
-	{ // Debug
-		v2f lwr; v2f upr;
-		v2f lwr1; v2f upr1;
-		v2f p0; v2f p1;
-		v2f vo;
-		v2f mouse_viewspace;
+		static v2f drag_origin; // x/y pixel
 
-		float rsize = size-view_zoom_extra;
-
-		v2_sub( (v2f){ -size + 0.1f, -size*r1 + 0.1f }, origin, lwr );
-		v2_sub( (v2f){  size - 0.1f,  size*r1 - 0.1f }, origin, upr );
-
-		v2_sub( (v2f){ -rsize, -rsize*r1 }, vt_target, lwr1 );
-		v2_sub( (v2f){  rsize,  rsize*r1 }, vt_target, upr1 );
-
-		vg_line_box( lwr, upr, 0xffffff00 );
-		vg_line_box( lwr1, upr1, 0xff00ff00 );
-
-		// Calculate vector towards mouse from vt_target
-		v2f mouse_delta;
-		v2_muls( vt_target, -1.0f, vo );
-
-		v2_sub( vt_target, vg_mouse_ws, mouse_delta );
-
-		vg_line( vo, vg_mouse_ws, 0xffffffff );
+		if( vg_get_button_down( "tertiary" ) )
+			v2_copy( vg_mouse, drag_origin );
+		else if( vg_get_button( "tertiary" ) )
+		{
+			// get offset
+			v2_sub( vg_mouse, drag_origin, drag_offset );
+			v2_div( drag_offset, (v2f){ vg_window_x, vg_window_y }, drag_offset );
+			v2_mul( drag_offset, (v2f){ size_current*2.0f, -size_current*r1*2.0f }, drag_offset );
+		}
+		else
+		{
+			v2_copy( result_view, view_point );
+			v2_copy( (v2f){0.0f,0.0f}, drag_offset );
+		}
+	}
 
-		// Mouse Locally
-		v2_div( vg_mouse, (v2f){ vg_window_x, vg_window_y }, mouse_viewspace );
-		mouse_viewspace[0] = mouse_viewspace[0]*rsize*2.0f;
-		mouse_viewspace[1] = (1.0f-mouse_viewspace[1])*rsize*2.0f*r1;
+	// Zooming
+	{
+		v2f mview_local;
+		v2f mview_new;
+		v2f mview_cur;
+		v2f mview_delta;
+		float rsize;
 
-		v2_add( lwr1, mouse_viewspace, mouse_viewspace );
+		rsize = size-view_zoom_extra;
 
-		vg_line( mouse_viewspace, (v2f){0.0f, 0.0f}, 0xff0000ff );
-	//}
+		v2_div( vg_mouse, (v2f){ vg_window_x*0.5f, vg_window_y*0.5f }, mview_local );
+		v2_add( (v2f){ -rsize, -rsize*r1 }, (v2f){ mview_local[0]*rsize, (2.0f-mview_local[1])*rsize*r1 }, mview_cur );
 
-		// Zoom
 		view_zoom_extra = vg_clampf( view_zoom_extra + vg_mouse_wheel[1], 0.0f, size - 4.0f );
-	
-		// Zoom offset adjust
-		rsize = size-view_zoom_extra;
-		v2_sub( (v2f){ -rsize, -rsize*r1 }, vt_target, lwr1 );
-		v2_sub( (v2f){  rsize,  rsize*r1 }, vt_target, upr1 );
-		
-		v2f mouse_viewspace_new;
-		v2_div( vg_mouse, (v2f){ vg_window_x, vg_window_y }, mouse_viewspace_new );
-		mouse_viewspace_new[0] = mouse_viewspace_new[0]*rsize*2.0f;
-		mouse_viewspace_new[1] = (1.0f-mouse_viewspace_new[1])*rsize*2.0f*r1;
 
-		v2_add( lwr1, mouse_viewspace_new, mouse_viewspace_new );
+		// Recalculate new position
+		rsize = size-view_zoom_extra;
+		v2_add( (v2f){ -rsize, -rsize*r1 }, (v2f){ mview_local[0]*rsize, (2.0f-mview_local[1])*rsize*r1 }, mview_new );
 
-		v2f zoom_offset;
-		v2_sub( mouse_viewspace, mouse_viewspace_new, zoom_offset );
-		v2_muladds( view_point, zoom_offset, -1.0f, view_point );
+		// Apply offset
+		v2_sub( mview_new, mview_cur, mview_delta );
+		v2_add( mview_delta, view_point, view_point );
 	}
-
+	
 	// Tilemap
 	// ========================================================================================================
 	if( !is_simulation_running() && !gui_want_mouse() )
@@ -1965,7 +1933,7 @@ static void vg_update(void)
 					{
 						fj = &world.fishes[j];
 						
-						if( (fj->state == k_fish_state_alive) )
+						if( fj->state == k_fish_state_alive )
 						{
 							v2i fi_prev;
 							v2i fj_prev;
-- 
2.25.1