diff options
Diffstat (limited to 'dragon/grid.rb')
| -rw-r--r-- | dragon/grid.rb | 40 |
1 files changed, 34 insertions, 6 deletions
diff --git a/dragon/grid.rb b/dragon/grid.rb index 2c808fc..2cfa04e 100644 --- a/dragon/grid.rb +++ b/dragon/grid.rb @@ -2,15 +2,20 @@ # Copyright 2019 DragonRuby LLC # MIT License # grid.rb has been released under MIT (*only this file*). +# Contributors outside of DragonRuby who also hold Copyright: _Tradam module GTK class Grid include Serialize - SCREEN_Y_DIRECTION = -1.0 + + # Returns which direction y is positive in. Negative means upward. + # + # @return [Float] `-1.0` or `1.0` + attr_accessor :screen_y_direction # The coordinate system currently in use. # - # @return [Symbol] `:bottom_left` or `:center` + # @return [Symbol] `:bottom_left`, `:center` or `:top_left` attr_accessor :name # Returns the "x" coordinate indicating the bottom of the screen. @@ -84,14 +89,14 @@ module GTK # # @return [Float] def transform_y y - @origin_y + y * SCREEN_Y_DIRECTION + @origin_y + y * screen_y_direction end # Returns `y` minus the origin "y". # # @return [Float] def untransform_y y - @origin_y + y * SCREEN_Y_DIRECTION + @origin_y + y * screen_y_direction end def ffi_draw @@ -121,7 +126,8 @@ module GTK @center_y = @runtime.logical_height.half @rect = [@left, @bottom, @runtime.logical_width, @runtime.logical_height].rect @center = [@center_x, @center_y].point - @ffi_draw.set_grid @origin_x, @origin_y, SCREEN_Y_DIRECTION + @screen_y_direction = -1.0 + @ffi_draw.set_grid @origin_x, @origin_y, @screen_y_direction end # Sets the rendering coordinate system to have its origin in the center. @@ -141,7 +147,29 @@ module GTK @center_y = 0.0 @rect = [@left, @bottom, @runtime.logical_width, @runtime.logical_height].rect @center = [@center_x, @center_y].point - @ffi_draw.set_grid @origin_x, @origin_y, SCREEN_Y_DIRECTION + @screen_y_direction = -1.0 + @ffi_draw.set_grid @origin_x, @origin_y, @screen_y_direction + end + + # Sets the rendering coordinate system to have its origin in the top left. + # + # @return [void] + # @gtk + def origin_top_left! + return if @name == :top_left + @name = :top_left + @origin_x = 0.0 + @origin_y = 0.0 + @left = 0.0 + @right = @runtime.logical_width + @top = 0.0 + @bottom = @runtime.logical_height + @center_x = @runtime.logical_width.half + @center_y = @runtime.logical_height.half + @rect = [@left, @runtime.logical_height, @runtime.logical_width, @top].rect + @center = [@center_x, @center_y].point + @screen_y_direction = 1.0 + @ffi_draw.set_grid @origin_x, @origin_y, @screen_y_direction end # The logical width used for rendering. |