gui/design: add option to draw N-point stars, hollow or filled or inverted, and change the main axis to orient in any direction

changelog.txt

@@ -16,6 +16,8 @@ Template for new versions:
 
 ## New Features
 
+- `gui/design`: add option to draw N-point stars, hollow or filled or inverted, and change the main axis to orient in any direction
+
 ## Fixes
 
 ## Misc Improvements

gui/design.lua

@@ -336,22 +336,29 @@ function Design:init()
         table.insert(mode_button_specs_selected, mode_option.value.button_selected_spec)
     end
 
-    local shape_tileset = dfhack.textures.loadTileset('hack/data/art/design.png', 8, 12, true)
+    local DESIGN_ICONS_WIDTH = 224 -- Must match design.png image width
+    local DESIGN_ICONS_HEIGHT = 72 -- Must match design.png image height
+    local DESIGN_ICON_ROW_COUNT = 2
+    local DESIGN_CHAR_WIDTH = 8
+    local DESIGN_CHAR_HEIGHT = 12
+    local shape_tileset = dfhack.textures.loadTileset('hack/data/art/design.png', DESIGN_CHAR_WIDTH, DESIGN_CHAR_HEIGHT, true)
+    local STRIDE = DESIGN_ICONS_WIDTH / DESIGN_CHAR_WIDTH
+    local CHARS_PER_ROW = DESIGN_ICONS_HEIGHT / (DESIGN_ICON_ROW_COUNT * DESIGN_CHAR_HEIGHT)
     local shape_options, shape_button_specs, shape_button_specs_selected = {}, {}, {}
     for _, shape in ipairs(shapes.all_shapes) do
         table.insert(shape_options, {label=shape.name, value=shape})
         table.insert(shape_button_specs, {
             chars=shape.button_chars,
             tileset=shape_tileset,
             tileset_offset=shape.texture_offset,
-            tileset_stride=24,
+            tileset_stride=STRIDE,
         })
         table.insert(shape_button_specs_selected, {
             chars=shape.button_chars,
             pens=COLOR_YELLOW,
             tileset=shape_tileset,
-            tileset_offset=shape.texture_offset+(24*3),
-            tileset_stride=24,
+            tileset_offset=shape.texture_offset+(STRIDE*CHARS_PER_ROW),
+            tileset_stride=STRIDE,
         })
     end
 

internal/design/shapes.lua

@@ -402,7 +402,9 @@ function Diag:has_point(x, y)
     end
 end
 
-Line = defclass(Line, Shape)
+LineDrawer = defclass(LineDrawer, Shape)
+
+Line = defclass(Line, LineDrawer)
 Line.ATTRS {
     name = "Line",
     extra_points = { { label = "Curve Point" }, { label = "Second Curve Point" } },
@@ -431,18 +433,19 @@ function Line:init()
     }
 end
 
-function Line:plot_bresenham(x0, y0, x1, y1, thickness)
+function LineDrawer:plot_bresenham(x0, y0, x1, y1, thickness)
     local dx = math.abs(x1 - x0)
     local dy = math.abs(y1 - y0)
     local sx = x0 < x1 and 1 or -1
     local sy = y0 < y1 and 1 or -1
-    local err = dx - dy
     local e2, x, y
 
     for i = 0, thickness - 1 do
         x = x0
         y = y0 + i
-        while true do
+        local err = dx - dy
+        local p = math.max(dx, dy)
+        while p >= 0 do
             for j = -math.floor(thickness / 2), math.ceil(thickness / 2) - 1 do
                 if not self.arr[x + j] then self.arr[x + j] = {} end
                 if not self.arr[x + j][y] then
@@ -451,7 +454,7 @@ function Line:plot_bresenham(x0, y0, x1, y1, thickness)
                 end
             end
 
-            if x == x1 and y == y1 + i then
+            if sx * x >= sx * x1 and sy * y >= sy * (y1 + i) then
                 break
             end
 
@@ -466,6 +469,7 @@ function Line:plot_bresenham(x0, y0, x1, y1, thickness)
                 err = err + dx
                 y = y + sy
             end
+            p = p - 1
         end
     end
 
@@ -684,7 +688,137 @@ function FreeForm:point_in_polygon(x, y)
     return inside
 end
 
+Star = defclass(Star, LineDrawer)
+Star.ATTRS {
+    name = "Star",
+    texture_offset = 25,
+    button_chars = util.make_ascii_button('*', 15),
+    extra_points = { { label = "Main Axis" } }
+}
+
+function Star:init()
+    self.options = {
+        hollow = {
+            name = "Hollow",
+            type = "bool",
+            value = false,
+            key = "CUSTOM_H",
+        },
+        thickness = {
+            name = "Line thickness",
+            type = "plusminus",
+            value = 1,
+            enabled = { "hollow", true },
+            min = 1,
+            max = function(shape) if not shape.height or not shape.width then
+                    return nil
+                else
+                    return math.ceil(math.min(shape.height, shape.width) / 2)
+
+                end
+            end,
+            keys = { "CUSTOM_T", "CUSTOM_SHIFT_T" },
+        },
+        total_points = {
+            name = "Total points",
+            type = "plusminus",
+            value = 5,
+            min = 3,
+            max = 100,
+            keys = { "CUSTOM_B", "CUSTOM_SHIFT_B" },
+        },
+        next_point_offset = {
+            name = "Next point offset",
+            type = "plusminus",
+            value = 2,
+            min = 1,
+            max = 100,
+            keys = { "CUSTOM_N", "CUSTOM_SHIFT_N" },
+        },
+    }
+end
+
+function Star:has_point(x, y)
+    if 1 < ((x-self.center.x) / self.center.x) ^ 2 + ((y-self.center.y) / self.center.y) ^ 2 then return false end
+
+    local inside = 0
+    for l = 1, self.options.total_points.value do
+        if x * self.lines[l].slope.x - self.lines[l].intercept.x < y * self.lines[l].slope.y - self.lines[l].intercept.y then
+            inside = inside + 1
+        else
+            inside = inside - 1
+        end
+    end
+    return self.threshold > 0 and inside > self.threshold or inside < self.threshold
+end
+
+function vmagnitude(point)
+    return math.sqrt(point.x * point.x + point.y * point.y)
+end
+
+function vnormalize(point)
+    local magnitude = vmagnitude(point)
+    return { x = point.x / magnitude, y = point.y / magnitude }
+end
+
+function add_offset(coord, offset)
+    return coord + (offset > 0 and math.floor(offset+0.5) or math.ceil(offset-0.5))
+end
+
+function Star:update(points, extra_points)
+    self.num_tiles = 0
+    self.points = copyall(points)
+    self.arr = {}
+    if #points < self.min_points then return end
+    self.threshold = self.options.total_points.value - 2 * self.options.next_point_offset.value
+    local top_left, bot_right = self:get_point_dims()
+    self.height = bot_right.y - top_left.y
+    self.width = bot_right.x - top_left.x
+    if self.height == 1 or self.width == 1 then return end
+    self.center = { x = self.width * 0.5, y = self.height * 0.5 }
+    local axes = {}
+
+    axes[1] = (#extra_points > 0) and { x = extra_points[1].x - self.center.x - top_left.x, y = extra_points[1].y - self.center.y - top_left.y } or { x = 0, y = -self.center.y }
+    if vmagnitude(axes[1]) < 0.5 then axes[1].y = -self.center.y end
+    axes[1] = vnormalize(axes[1])
+
+    for a = 2, self.options.total_points.value do
+        local angle = math.pi * (a - 1.0) * 2.0 / self.options.total_points.value
+        axes[a] = { x = math.cos(angle) * axes[1].x - math.sin(angle) * axes[1].y, y = math.sin(angle) * axes[1].x + math.cos(angle) * axes[1].y }
+    end
+
+    local thickness = 1
+    if self.options.hollow.value then
+        thickness = self.options.thickness.value
+    end
+
+    self.lines = {}
+    for l = 1, self.options.total_points.value do
+        local p1 = { x = self.center.x + axes[l].x * self.width * 0.5, y = self.center.y + axes[l].y * self.height * 0.5 }
+        local next_axis = axes[(l-1+self.options.next_point_offset.value) % self.options.total_points.value + 1]
+        local p2 = { x = self.center.x + next_axis.x * self.width * 0.5, y = self.center.y + next_axis.y * self.height * 0.5 }
+        self.lines[l] = { slope = { x = p2.y - p1.y, y = p2.x - p1.x }, intercept = { x = (p2.y - p1.y) * p1.x, y = (p2.x - p1.x) * p1.y } }
+        self:plot_bresenham(add_offset(top_left.x, p1.x), add_offset(top_left.y, p1.y), add_offset(top_left.x, p2.x), add_offset(top_left.y, p2.y), thickness)
+        self:plot_bresenham(add_offset(top_left.x, p2.x), add_offset(top_left.y, p2.y), add_offset(top_left.x, p1.x), add_offset(top_left.y, p1.y), thickness)
+    end
+
+    if not self.options.hollow.value or self.invert then
+        for x = top_left.x, bot_right.x do
+            if not self.arr[x] then self.arr[x] = {} end
+            for y = top_left.y, bot_right.y do
+                local value = self.arr[x][y] or (not self.options.hollow.value and self:has_point(x - top_left.x, y - top_left.y))
+                if self.invert then
+                    self.arr[x][y] = not value
+                else
+                    self.arr[x][y] = value
+                end
+
+                self.num_tiles = self.num_tiles + (self.arr[x][y] and 1 or 0)
+            end
+        end
+    end
+end
 -- module users can get shapes through this global, shape option values
 -- persist in these as long as the module is loaded
 -- idk enough lua to know if this is okay to do or not
-all_shapes = { Rectangle {}, Ellipse {}, Rows {}, Diag {}, Line {}, FreeForm {} }
+all_shapes = { Rectangle {}, Ellipse {}, Rows {}, Diag {}, Line {}, FreeForm {}, Star {} }