-- primitives for editing drawings Drawing = {} geom = require 'geom' -- All drawings span 100% of some conceptual 'page width' and divide it up -- into 256 parts. function Drawing.draw(line) local pmx,pmy = love.mouse.getX(), love.mouse.getY() if pmx < 16+Line_width and pmy > line.y and pmy < line.y+Drawing.pixels(line.h) then love.graphics.setColor(0.75,0.75,0.75) love.graphics.rectangle('line', 16,line.y, Line_width,Drawing.pixels(line.h)) if icon[Current_drawing_mode] then icon[Current_drawing_mode](16+Line_width-20, line.y+4) else icon[Previous_drawing_mode](16+Line_width-20, line.y+4) end if love.mouse.isDown('1') and love.keyboard.isDown('h') then draw_help_with_mouse_pressed(line) return end end if line.show_help then draw_help_without_mouse_pressed(line) return end local mx,my = Drawing.coord(pmx-16), Drawing.coord(pmy-line.y) for _,shape in ipairs(line.shapes) do assert(shape) if geom.on_shape(mx,my, line, shape) then love.graphics.setColor(1,0,0) else love.graphics.setColor(0,0,0) end Drawing.draw_shape(16,line.y, line, shape) end for i,p in ipairs(line.points) do if p.deleted == nil then if Drawing.near(p, mx,my) then love.graphics.setColor(1,0,0) love.graphics.circle('line', Drawing.pixels(p.x)+16,Drawing.pixels(p.y)+line.y, 4) else love.graphics.setColor(0,0,0) love.graphics.circle('fill', Drawing.pixels(p.x)+16,Drawing.pixels(p.y)+line.y, 2) end if p.name then -- todo: clip local x,y = Drawing.pixels(p.x)+16+5, Drawing.pixels(p.y)+line.y+5 love.graphics.print(p.name, x,y) if Current_drawing_mode == 'name' and i == line.pending.target_point then -- create a faint red box for the name love.graphics.setColor(1,0,0,0.1) local name_text -- TODO: avoid computing name width on every repaint if p.name == '' then name_text = App.newText(love.graphics.getFont(), 'm') -- 1em else name_text = App.newText(love.graphics.getFont(), p.name) end love.graphics.rectangle('fill', x,y, App.width(name_text), Line_height) end end end end love.graphics.setColor(0.75,0.75,0.75) Drawing.draw_pending_shape(16,line.y, line) end function Drawing.draw_shape(left,top, drawing, shape) if shape.mode == 'freehand' then local prev = nil for _,point in ipairs(shape.points) do if prev then love.graphics.line(Drawing.pixels(prev.x)+left,Drawing.pixels(prev.y)+top, Drawing.pixels(point.x)+left,Drawing.pixels(point.y)+top) end prev = point end elseif shape.mode == 'line' or shape.mode == 'manhattan' then local p1 = drawing.points[shape.p1] local p2 = drawing.points[shape.p2] love.graphics.line(Drawing.pixels(p1.x)+left,Drawing.pixels(p1.y)+top, Drawing.pixels(p2.x)+left,Drawing.pixels(p2.y)+top) elseif shape.mode == 'polygon' or shape.mode == 'rectangle' or shape.mode == 'square' then local prev = nil for _,point in ipairs(shape.vertices) do local curr = drawing.points[point] if prev then love.graphics.line(Drawing.pixels(prev.x)+left,Drawing.pixels(prev.y)+top, Drawing.pixels(curr.x)+left,Drawing.pixels(curr.y)+top) end prev = curr end -- close the loop local curr = drawing.points[shape.vertices[1]] love.graphics.line(Drawing.pixels(prev.x)+left,Drawing.pixels(prev.y)+top, Drawing.pixels(curr.x)+left,Drawing.pixels(curr.y)+top) elseif shape.mode == 'circle' then -- todo: clip local center = drawing.points[shape.center] love.graphics.circle('line', Drawing.pixels(center.x)+left,Drawing.pixels(center.y)+top, Drawing.pixels(shape.radius)) elseif shape.mode == 'arc' then local center = drawing.points[shape.center] love.graphics.arc('line', 'open', Drawing.pixels(center.x)+left,Drawing.pixels(center.y)+top, Drawing.pixels(shape.radius), shape.start_angle, shape.end_angle, 360) elseif shape.mode == 'deleted' then -- ignore else print(shape.mode) assert(false) end end function Drawing.draw_pending_shape(left,top, drawing) local shape = drawing.pending if shape.mode == nil then -- nothing pending elseif shape.mode == 'freehand' then Drawing.draw_shape(left,top, drawing, shape) elseif shape.mode == 'line' then local mx,my = Drawing.coord(love.mouse.getX()-left), Drawing.coord(love.mouse.getY()-top) if mx < 0 or mx >= 256 or my < 0 or my >= drawing.h then return end local p1 = drawing.points[shape.p1] love.graphics.line(Drawing.pixels(p1.x)+left,Drawing.pixels(p1.y)+top, Drawing.pixels(mx)+left,Drawing.pixels(my)+top) elseif shape.mode == 'manhattan' then local mx,my = Drawing.coord(love.mouse.getX()-left), Drawing.coord(love.mouse.getY()-top) if mx < 0 or mx >= 256 or my < 0 or my >= drawing.h then return end local p1 = drawing.points[shape.p1] if math.abs(mx-p1.x) > math.abs(my-p1.y) then love.graphics.line(Drawing.pixels(p1.x)+left,Drawing.pixels(p1.y)+top, Drawing.pixels(mx)+left,Drawing.pixels(p1.y)+top) else love.graphics.line(Drawing.pixels(p1.x)+left,Drawing.pixels(p1.y)+top, Drawing.pixels(p1.x)+left,Drawing.pixels(my)+top) end elseif shape.mode == 'polygon' then -- don't close the loop on a pending polygon local prev = nil for _,point in ipairs(shape.vertices) do local curr = drawing.points[point] if prev then love.graphics.line(Drawing.pixels(prev.x)+left,Drawing.pixels(prev.y)+top, Drawing.pixels(curr.x)+left,Drawing.pixels(curr.y)+top) end prev = curr end love.graphics.line(Drawing.pixels(prev.x)+left,Drawing.pixels(prev.y)+top, love.mouse.getX(),love.mouse.getY()) elseif shape.mode == 'rectangle' then local pmx,pmy = love.mouse.getX(), love.mouse.getY() local first = drawing.points[shape.vertices[1]] if #shape.vertices == 1 then love.graphics.line(Drawing.pixels(first.x)+left,Drawing.pixels(first.y)+top, pmx,pmy) return end local second = drawing.points[shape.vertices[2]] local mx,my = Drawing.coord(pmx-left), Drawing.coord(pmy-top) local thirdx,thirdy, fourthx,fourthy = Drawing.complete_rectangle(first.x,first.y, second.x,second.y, mx,my) love.graphics.line(Drawing.pixels(first.x)+left,Drawing.pixels(first.y)+top, Drawing.pixels(second.x)+left,Drawing.pixels(second.y)+top) love.graphics.line(Drawing.pixels(second.x)+left,Drawing.pixels(second.y)+top, Drawing.pixels(thirdx)+left,Drawing.pixels(thirdy)+top) love.graphics.line(Drawing.pixels(thirdx)+left,Drawing.pixels(thirdy)+top, Drawing.pixels(fourthx)+left,Drawing.pixels(fourthy)+top) love.graphics.line(Drawing.pixels(fourthx)+left,Drawing.pixels(fourthy)+top, Drawing.pixels(first.x)+left,Drawing.pixels(first.y)+top) elseif shape.mode == 'square' then local pmx,pmy = love.mouse.getX(), love.mouse.getY() local first = drawing.points[shape.vertices[1]] if #shape.vertices == 1 then love.graphics.line(Drawing.pixels(first.x)+left,Drawing.pixels(first.y)+top, pmx,pmy) return end local second = drawing.points[shape.vertices[2]] local mx,my = Drawing.coord(pmx-left), Drawing.coord(pmy-top) local thirdx,thirdy, fourthx,fourthy = Drawing.complete_square(first.x,first.y, second.x,second.y, mx,my) love.graphics.line(Drawing.pixels(first.x)+left,Drawing.pixels(first.y)+top, Drawing.pixels(second.x)+left,Drawing.pixels(second.y)+top) love.graphics.line(Drawing.pixels(second.x)+left,Drawing.pixels(second.y)+top, Drawing.pixels(thirdx)+left,Drawing.pixels(thirdy)+top) love.graphics.line(Drawing.pixels(thirdx)+left,Drawing.pixels(thirdy)+top, Drawing.pixels(fourthx)+left,Drawing.pixels(fourthy)+top) love.graphics.line(Drawing.pixels(fourthx)+left,Drawing.pixels(fourthy)+top, Drawing.pixels(first.x)+left,Drawing.pixels(first.y)+top) elseif shape.mode == 'circle' then local center = drawing.points[shape.center] local mx,my = Drawing.coord(love.mouse.getX()-left), Drawing.coord(love.mouse.getY()-top) if mx < 0 or mx >= 256 or my < 0 or my >= drawing.h then return end local cx,cy = Drawing.pixels(center.x)+left, Drawing.pixels(center.y)+top love.graphics.circle('line', cx,cy, geom.dist(cx,cy, love.mouse.getX(),love.mouse.getY())) elseif shape.mode == 'arc' then local center = drawing.points[shape.center] local mx,my = Drawing.coord(love.mouse.getX()-left), Drawing.coord(love.mouse.getY()-top) if mx < 0 or mx >= 256 or my < 0 or my >= drawing.h then return end shape.end_angle = geom.angle_with_hint(center.x,center.y, mx,my, shape.end_angle) local cx,cy = Drawing.pixels(center.x)+left, Drawing.pixels(center.y)+top love.graphics.arc('line', 'open', cx,cy, Drawing.pixels(shape.radius), shape.start_angle, shape.end_angle, 360) elseif shape.mode == 'move' then -- nothing pending; changes are immediately committed elseif shape.mode == 'name' then -- nothing pending; changes are immediately committed else print(shape.mode) assert(false) end end function Drawing.in_drawing(drawing, x,y) if drawing.y == nil then return false end -- outside current page return y >= drawing.y and y < drawing.y + Drawing.pixels(drawing.h) and x >= 16 and x < 16+Line_width end function Drawing.mouse_pressed(drawing, x,y, button) Drawing.before = snapshot() if Current_drawing_mode == 'freehand' then drawing.pending = {mode=Current_drawing_mode, points={{x=Drawing.coord(x-16), y=Drawing.coord(y-drawing.y)}}} elseif Current_drawing_mode == 'line' or Current_drawing_mode == 'manhattan' then local j = Drawing.insert_point(drawing.points, Drawing.coord(x-16), Drawing.coord(y-drawing.y)) drawing.pending = {mode=Current_drawing_mode, p1=j} elseif Current_drawing_mode == 'polygon' or Current_drawing_mode == 'rectangle' or Current_drawing_mode == 'square' then local j = Drawing.insert_point(drawing.points, Drawing.coord(x-16), Drawing.coord(y-drawing.y)) drawing.pending = {mode=Current_drawing_mode, vertices={j}} elseif Current_drawing_mode == 'circle' then local j = Drawing.insert_point(drawing.points, Drawing.coord(x-16), Drawing.coord(y-drawing.y)) drawing.pending = {mode=Current_drawing_mode, center=j} elseif Current_drawing_mode == 'move' then -- all the action is in mouse_released elseif Current_drawing_mode == 'name' then -- nothing else print(Current_drawing_mode) assert(false) end Lines.current = drawing end -- a couple of operations on drawings need to constantly check the state of the mouse function Drawing.update() if Lines.current == nil then return end local drawing = Lines.current assert(drawing.mode == 'drawing') local x, y = love.mouse.getX(), love.mouse.getY() if love.mouse.isDown('1') then if Drawing.in_drawing(drawing, x,y) then if drawing.pending.mode == 'freehand' then table.insert(drawing.pending.points, {x=Drawing.coord(love.mouse.getX()-16), y=Drawing.coord(love.mouse.getY()-drawing.y)}) elseif drawing.pending.mode == 'move' then local mx,my = Drawing.coord(x-16), Drawing.coord(y-drawing.y) drawing.pending.target_point.x = mx drawing.pending.target_point.y = my end end elseif Current_drawing_mode == 'move' then if Drawing.in_drawing(drawing, x, y) then local mx,my = Drawing.coord(x-16), Drawing.coord(y-drawing.y) drawing.pending.target_point.x = mx drawing.pending.target_point.y = my end else -- do nothing end end function Drawing.mouse_released(x,y, button) if Current_drawing_mode == 'move' then Current_drawing_mode = Previous_drawing_mode Previous_drawing_mode = nil elseif Lines.current then local drawing = Lines.current if drawing.pending then if drawing.pending.mode == 'freehand' then -- the last point added during update is good enough table.insert(drawing.shapes, drawing.pending) elseif drawing.pending.mode == 'line' then local mx,my = Drawing.coord(x-16), Drawing.coord(y-drawing.y) if mx >= 0 and mx < 256 and my >= 0 and my < drawing.h then local j = Drawing.insert_point(drawing.points, mx,my) drawing.pending.p2 = j table.insert(drawing.shapes, drawing.pending) end elseif drawing.pending.mode == 'manhattan' then local p1 = drawing.points[drawing.pending.p1] local mx,my = Drawing.coord(x-16), Drawing.coord(y-drawing.y) if mx >= 0 and mx < 256 and my >= 0 and my < drawing.h then if math.abs(mx-p1.x) > math.abs(my-p1.y) then local j = Drawing.insert_point(drawing.points, mx, p1.y) drawing.pending.p2 = j else local j = Drawing.insert_point(drawing.points, p1.x, my) drawing.pending.p2 = j end local p2 = drawing.points[drawing.pending.p2] love.mouse.setPosition(16+Drawing.pixels(p2.x), drawing.y+Drawing.pixels(p2.y)) table.insert(drawing.shapes, drawing.pending) end elseif drawing.pending.mode == 'polygon' then local mx,my = Drawing.coord(x-16), Drawing.coord(y-drawing.y) if mx >= 0 and mx < 256 and my >= 0 and my < drawing.h then table.insert(drawing.pending.vertices, Drawing.insert_point(drawing.points, mx,my)) table.insert(drawing.shapes, drawing.pending) end elseif drawing.pending.mode == 'rectangle' then assert(#drawing.pending.vertices <= 2) if #drawing.pending.vertices == 2 then local mx,my = Drawing.coord(x-16), Drawing.coord(y-drawing.y) if mx >= 0 and mx < 256 and my >= 0 and my < drawing.h then local first = drawing.points[drawing.pending.vertices[1]] local second = drawing.points[drawing.pending.vertices[2]] local thirdx,thirdy, fourthx,fourthy = Drawing.complete_rectangle(first.x,first.y, second.x,second.y, mx,my) table.insert(drawing.pending.vertices, Drawing.insert_point(drawing.points, thirdx,thirdy)) table.insert(drawing.pending.vertices, Drawing.insert_point(drawing.points, fourthx,fourthy)) table.insert(drawing.shapes, drawing.pending) end else -- too few points; draw nothing end elseif drawing.pending.mode == 'square' then assert(#drawing.pending.vertices <= 2) if #drawing.pending.vertices == 2 then local mx,my = Drawing.coord(x-16), Drawing.coord(y-drawing.y) if mx >= 0 and mx < 256 and my >= 0 and my < drawing.h then local first = drawing.points[drawing.pending.vertices[1]] local second = drawing.points[drawing.pending.vertices[2]] local thirdx,thirdy, fourthx,fourthy = Drawing.complete_square(first.x,first.y, second.x,second.y, mx,my) table.insert(drawing.pending.vertices, Drawing.insert_point(drawing.points, thirdx,thirdy)) table.insert(drawing.pending.vertices, Drawing.insert_point(drawing.points, fourthx,fourthy)) table.insert(drawing.shapes, drawing.pending) end end elseif drawing.pending.mode == 'circle' then local mx,my = Drawing.coord(x-16), Drawing.coord(y-drawing.y) if mx >= 0 and mx < 256 and my >= 0 and my < drawing.h then local center = drawing.points[drawing.pending.center] drawing.pending.radius = geom.dist(center.x,center.y, mx,my) table.insert(drawing.shapes, drawing.pending) end elseif drawing.pending.mode == 'arc' then local mx,my = Drawing.coord(x-16), Drawing.coord(y-drawing.y) if mx >= 0 and mx < 256 and my >= 0 and my < drawing.h then local center = drawing.points[drawing.pending.center] drawing.pending.end_angle = geom.angle_with_hint(center.x,center.y, mx,my, drawing.pending.end_angle) table.insert(drawing.shapes, drawing.pending) end elseif drawing.pending.mode == 'move' then -- drop it elseif drawing.pending.mode == 'name' then -- drop it else print(drawing.pending.mode) assert(false) end Lines.current.pending = {} Lines.current = nil end end save_to_disk(Lines, Filename) if Drawing.before then record_undo_event({before=Drawing.before, after=snapshot()}) Drawing.before = nil end end function Drawing.keychord_pressed(chord) if chord == 'C-p' and not love.mouse.isDown('1') then Current_drawing_mode = 'freehand' elseif chord == 'C-g' and not love.mouse.isDown('1') then Current_drawing_mode = 'polygon' elseif love.mouse.isDown('1') and chord == 'g' then Current_drawing_mode = 'polygon' local drawing = Drawing.current_drawing() if drawing.pending.mode == 'freehand' then drawing.pending.vertices = {Drawing.insert_point(drawing.points, drawing.pending.points[1].x, drawing.pending.points[1].y)} elseif drawing.pending.mode == 'line' or drawing.pending.mode == 'manhattan' then if drawing.pending.vertices == nil then drawing.pending.vertices = {drawing.pending.p1} end elseif drawing.pending.mode == 'square' or drawing.pending.mode == 'rectangle' then -- reuse existing vertices elseif drawing.pending.mode == 'circle' or drawing.pending.mode == 'arc' then drawing.pending.vertices = {drawing.pending.center} end drawing.pending.mode = 'polygon' elseif chord == 'C-r' and not love.mouse.isDown('1') then Current_drawing_mode = 'rectangle' elseif love.mouse.isDown('1') and chord == 'r' then Current_drawing_mode = 'rectangle' local drawing = Drawing.current_drawing() if drawing.pending.mode == 'freehand' then drawing.pending.vertices = {Drawing.insert_point(drawing.points, drawing.pending.points[1].x, drawing.pending.points[1].y)} elseif drawing.pending.mode == 'line' or drawing.pending.mode == 'manhattan' then if drawing.pending.vertices == nil then drawing.pending.vertices = {drawing.pending.p1} end elseif drawing.pending.mode == 'circle' or drawing.pending.mode == 'arc' then drawing.pending.vertices = {drawing.pending.center} elseif drawing.pending.mode == 'polygon' or drawing.pending.mode == 'square' then -- reuse existing (1-2) vertices end drawing.pending.mode = 'rectangle' elseif chord == 'C-s' and not love.mouse.isDown('1') then Current_drawing_mode = 'square' elseif love.mouse.isDown('1') and chord == 's' then Current_drawing_mode = 'square' local drawing = Drawing.current_drawing() if drawing.pending.mode == 'freehand' then drawing.pending.vertices = {Drawing.insert_point(drawing.points, drawing.pending.points[1].x, drawing.pending.points[1].y)} elseif drawing.pending.mode == 'line' or drawing.pending.mode == 'manhattan' then if drawing.pending.vertices == nil then drawing.pending.vertices = {drawing.pending.p1} end elseif drawing.pending.mode == 'circle' or drawing.pending.mode == 'arc' then drawing.pending.vertices = {drawing.pending.center} elseif drawing.pending.mode == 'rectangle' then -- reuse existing (1-2) vertices elseif drawing.pending.mode == 'polygon' then while #drawing.pending.vertices > 2 do table.remove(drawing.pending.vertices) end end drawing.pending.mode = 'square' elseif love.mouse.isDown('1') and chord == 'p' and (Current_drawing_mode == 'polygon' or Current_drawing_mode == 'rectangle' or Current_drawing_mode == 'square') then local drawing = Drawing.current_drawing() local mx,my = Drawing.coord(love.mouse.getX()-16), Drawing.coord(love.mouse.getY()-drawing.y) local j = Drawing.insert_point(drawing.points, mx,my) table.insert(drawing.pending.vertices, j) elseif chord == 'C-c' and not love.mouse.isDown('1') then Current_drawing_mode = 'circle' elseif love.mouse.isDown('1') and chord == 'a' and Current_drawing_mode == 'circle' then local drawing = Drawing.current_drawing() drawing.pending.mode = 'arc' local mx,my = Drawing.coord(love.mouse.getX()-16), Drawing.coord(love.mouse.getY()-drawing.y) local j = Drawing.insert_point(drawing.points, mx,my) local center = drawing.points[drawing.pending.center] drawing.pending.radius = geom.dist(center.x,center.y, mx,my) drawing.pending.start_angle = geom.angle(center.x,center.y, mx,my) elseif love.mouse.isDown('1') and chord == 'c' then Current_drawing_mode = 'circle' local drawing = Drawing.current_drawing() if drawing.pending.mode == 'freehand' then drawing.pending.center = Drawing.insert_point(drawing.points, drawing.pending.points[1].x, drawing.pending.points[1].y) elseif drawing.pending.mode == 'line' or drawing.pending.mode == 'manhattan' then drawing.pending.center = drawing.pending.p1 elseif drawing.pending.mode == 'polygon' or drawing.pending.mode == 'rectangle' or drawing.pending.mode == 'square' then drawing.pending.center = drawing.pending.vertices[1] end drawing.pending.mode = 'circle' elseif love.mouse.isDown('1') and chord == 'l' then Current_drawing_mode = 'line' local drawing = Drawing.current_drawing() if drawing.pending.mode == 'freehand' then drawing.pending.p1 = Drawing.insert_point(drawing.points, drawing.pending.points[1].x, drawing.pending.points[1].y) elseif drawing.pending.mode == 'circle' or drawing.pending.mode == 'arc' then drawing.pending.p1 = drawing.pending.center elseif drawing.pending.mode == 'polygon' or drawing.pending.mode == 'rectangle' or drawing.pending.mode == 'square' then drawing.pending.p1 = drawing.pending.vertices[1] end drawing.pending.mode = 'line' elseif chord == 'C-l' and not love.mouse.isDown('1') then Current_drawing_mode = 'line' elseif love.mouse.isDown('1') and chord == 'm' then Current_drawing_mode = 'manhattan' local drawing = Drawing.select_drawing_at_mouse() if drawing.pending.mode == 'freehand' then drawing.pending.p1 = Drawing.insert_point(drawing.points, drawing.pending.points[1].x, drawing.pending.points[1].y) elseif drawing.pending.mode == 'line' then -- do nothing elseif drawing.pending.mode == 'polygon' or drawing.pending.mode == 'rectangle' or drawing.pending.mode == 'square' then drawing.pending.p1 = drawing.pending.vertices[1] elseif drawing.pending.mode == 'circle' or drawing.pending.mode == 'arc' then drawing.pending.p1 = drawing.pending.center end drawing.pending.mode = 'manhattan' elseif chord == 'C-m' and not love.mouse.isDown('1') then Current_drawing_mode = 'manhattan' elseif chord == 'C-s' and not love.mouse.isDown('1') then local drawing,_,shape = Drawing.select_shape_at_mouse() if drawing then smoothen(shape) end elseif chord == 'C-v' and not love.mouse.isDown('1') then local drawing,_,p = Drawing.select_point_at_mouse() if drawing then if Previous_drawing_mode == nil then Previous_drawing_mode = Current_drawing_mode end Current_drawing_mode = 'move' drawing.pending = {mode=Current_drawing_mode, target_point=p} Lines.current = drawing end elseif love.mouse.isDown('1') and chord == 'v' then local drawing,_,p = Drawing.select_point_at_mouse() if drawing then if Previous_drawing_mode == nil then Previous_drawing_mode = Current_drawing_mode end Current_drawing_mode = 'move' drawing.pending = {mode=Current_drawing_mode, target_point=p} Lines.current = drawing end elseif chord == 'C-n' and not love.mouse.isDown('1') then local drawing,point_index,p = Drawing.select_point_at_mouse() if drawing then if Previous_drawing_mode == nil then -- don't clobber Previous_drawing_mode = Current_drawing_mode end Current_drawing_mode = 'name' p.name = '' drawing.pending = {mode=Current_drawing_mode, target_point=point_index} Lines.current = drawing end elseif chord == 'C-d' and not love.mouse.isDown('1') then local drawing,i,p = Drawing.select_point_at_mouse() if drawing then for _,shape in ipairs(drawing.shapes) do if Drawing.contains_point(shape, i) then if shape.mode == 'polygon' then local idx = table.find(shape.vertices, i) assert(idx) table.remove(shape.vertices, idx) if #shape.vertices < 3 then shape.mode = 'deleted' end else shape.mode = 'deleted' end end end drawing.points[i].deleted = true end local drawing,_,shape = Drawing.select_shape_at_mouse() if drawing then shape.mode = 'deleted' end elseif chord == 'C-h' and not love.mouse.isDown('1') then local drawing = Drawing.select_drawing_at_mouse() if drawing then drawing.show_help = true end end end function Drawing.complete_rectangle(firstx,firsty, secondx,secondy, x,y) if firstx == secondx then return x,secondy, x,firsty end if firsty == secondy then return secondx,y, firstx,y end local first_slope = (secondy-firsty)/(secondx-firstx) -- slope of second edge: -- -1/first_slope -- equation of line containing the second edge: -- y-secondy = -1/first_slope*(x-secondx) -- => 1/first_slope*x + y + (- secondy - secondx/first_slope) = 0 -- now we want to find the point on this line that's closest to the mouse pointer. -- https://en.wikipedia.org/wiki/Distance_from_a_point_to_a_line#Line_defined_by_an_equation local a = 1/first_slope local c = -secondy - secondx/first_slope local thirdx = ((x-a*y) - a*c) / (a*a + 1) local thirdy = (a*(-x + a*y) - c) / (a*a + 1) -- slope of third edge = first_slope -- equation of line containing third edge: -- y - thirdy = first_slope*(x-thirdx) -- => -first_slope*x + y + (-thirdy + thirdx*first_slope) = 0 -- now we want to find the point on this line that's closest to the first point local a = -first_slope local c = -thirdy + thirdx*first_slope local fourthx = ((firstx-a*firsty) - a*c) / (a*a + 1) local fourthy = (a*(-firstx + a*firsty) - c) / (a*a + 1) return thirdx,thirdy, fourthx,fourthy end function Drawing.complete_square(firstx,firsty, secondx,secondy, x,y) -- use x,y only to decide which side of the first edge to complete the square on local deltax = secondx-firstx local deltay = secondy-firsty local thirdx = secondx+deltay local thirdy = secondy-deltax if not geom.same_side(firstx,firsty, secondx,secondy, thirdx,thirdy, x,y) then deltax = -deltax deltay = -deltay thirdx = secondx+deltay thirdy = secondy-deltax end local fourthx = firstx+deltay local fourthy = firsty-deltax return thirdx,thirdy, fourthx,fourthy end function Drawing.current_drawing() local x, y = love.mouse.getX(), love.mouse.getY() for _,drawing in ipairs(Lines) do if drawing.mode == 'drawing' then if Drawing.in_drawing(drawing, x,y) then return drawing end end end return nil end function Drawing.select_shape_at_mouse() for _,drawing in ipairs(Lines) do if drawing.mode == 'drawing' then local x, y = love.mouse.getX(), love.mouse.getY() if Drawing.in_drawing(drawing, x,y) then local mx,my = Drawing.coord(x-16), Drawing.coord(y-drawing.y) for i,shape in ipairs(drawing.shapes) do assert(shape) if geom.on_shape(mx,my, drawing, shape) then return drawing,i,shape end end end end end end function Drawing.select_point_at_mouse() for _,drawing in ipairs(Lines) do if drawing.mode == 'drawing' then local x, y = love.mouse.getX(), love.mouse.getY() if Drawing.in_drawing(drawing, x,y) then local mx,my = Drawing.coord(x-16), Drawing.coord(y-drawing.y) for i,point in ipairs(drawing.points) do assert(point) if Drawing.near(point, mx,my) then return drawing,i,point end end end end end end function Drawing.select_drawing_at_mouse() for _,drawing in ipairs(Lines) do if drawing.mode == 'drawing' then local x, y = love.mouse.getX(), love.mouse.getY() if Drawing.in_drawing(drawing, x,y) then return drawing end end end end function Drawing.contains_point(shape, p) if shape.mode == 'freehand' then -- not supported elseif shape.mode == 'line' or shape.mode == 'manhattan' then return shape.p1 == p or shape.p2 == p elseif shape.mode == 'polygon' or shape.mode == 'rectangle' or shape.mode == 'square' then return table.find(shape.vertices, p) elseif shape.mode == 'circle' then return shape.center == p elseif shape.mode == 'arc' then return shape.center == p -- ugh, how to support angles elseif shape.mode == 'deleted' then -- already done else print(shape.mode) assert(false) end end function Drawing.convert_line(drawing, shape) -- Perhaps we should do a more sophisticated "simple linear regression" -- here: -- https://en.wikipedia.org/wiki/Linear_regression#Simple_and_multiple_linear_regression -- But this works well enough for close-to-linear strokes. assert(shape.mode == 'freehand') shape.mode = 'line' shape.p1 = insert_point(drawing.points, shape.points[1].x, shape.points[1].y) local n = #shape.points shape.p2 = insert_point(drawing.points, shape.points[n].x, shape.points[n].y) end -- turn a line either horizontal or vertical function Drawing.convert_horvert(drawing, shape) if shape.mode == 'freehand' then Drawing.convert_line(shape) end assert(shape.mode == 'line') local p1 = drawing.points[shape.p1] local p2 = drawing.points[shape.p2] if math.abs(p1.x-p2.x) > math.abs(p1.y-p2.y) then p2.y = p1.y else p2.x = p1.x end end function Drawing.smoothen(shape) assert(shape.mode == 'freehand') for _=1,7 do for i=2,#shape.points-1 do local a = shape.points[i-1] local b = shape.points[i] local c = shape.points[i+1] b.x = (a.x + b.x + c.x)/3 b.y = (a.y + b.y + c.y)/3 end end end function Drawing.insert_point(points, x,y) for i,point in ipairs(points) do if Drawing.near(point, x,y) then return i end end table.insert(points, {x=x, y=y}) return #points end function Drawing.near(point, x,y) local px,py = Drawing.pixels(x),Drawing.pixels(y) local cx,cy = Drawing.pixels(point.x), Drawing.pixels(point.y) return (cx-px)*(cx-px) + (cy-py)*(cy-py) < 16 end function Drawing.pixels(n) -- parts to pixels return math.floor(n*Line_width/256) end function Drawing.coord(n) -- pixels to parts return math.floor(n*256/Line_width) end function table.find(h, x) for k,v in pairs(h) do if v == x then return k end end end return Drawing