Fix Fiddle-style struct access

Author: kojix2

lib/gr.rb

@@ -1119,41 +1119,41 @@ def inqtextext(x, y, string)
     def axis(option, min: Float::NAN, max: Float::NAN, tick: Float::NAN, org: Float::NAN, position: Float::NAN, major_count: 1,
              tick_size: Float::NAN, label_position: Float::NAN, draw_axis_line: 1, label_orientation: 0)
       ax = FFI::Axis.malloc
-      ax.min = min
-      ax.max = max
-      ax.tick = tick
-      ax.org = org
-      ax.position = position
-      ax.major_count = major_count
-      ax.tick_size = tick_size
-      ax.label_position = label_position
-      ax.draw_axis_line = draw_axis_line
-      ax.label_orientation = label_orientation
-      ax.ticks = FFI::Pointer::NULL
-      ax.num_ticks = 0
-      ax.tick_labels = FFI::Pointer::NULL
-      ax.num_tick_labels = 0
+      ax[:min] = min
+      ax[:max] = max
+      ax[:tick] = tick
+      ax[:org] = org
+      ax[:position] = position
+      ax[:major_count] = major_count
+      ax[:tick_size] = tick_size
+      ax[:label_position] = label_position
+      ax[:draw_axis_line] = draw_axis_line
+      ax[:label_orientation] = label_orientation
+      ax[:ticks] = 0
+      ax[:num_ticks] = 0
+      ax[:tick_labels] = 0
+      ax[:num_tick_labels] = 0
       super(option, ax)
       ax
     end
 
     def drawaxis(option, min: Float::NAN, max: Float::NAN, tick: Float::NAN, org: Float::NAN, position: Float::NAN,
                  major_count: 1, tick_size: Float::NAN, label_position: Float::NAN, draw_axis_line: 1, label_orientation: 0)
       ax = FFI::Axis.malloc
-      ax.min = min
-      ax.max = max
-      ax.tick = tick
-      ax.org = org
-      ax.position = position
-      ax.major_count = major_count
-      ax.tick_size = tick_size
-      ax.label_position = label_position
-      ax.draw_axis_line = draw_axis_line
-      ax.label_orientation = label_orientation
-      ax.ticks = FFI::Pointer::NULL
-      ax.num_ticks = 0
-      ax.tick_labels = FFI::Pointer::NULL
-      ax.num_tick_labels = 0
+      ax[:min] = min
+      ax[:max] = max
+      ax[:tick] = tick
+      ax[:org] = org
+      ax[:position] = position
+      ax[:major_count] = major_count
+      ax[:tick_size] = tick_size
+      ax[:label_position] = label_position
+      ax[:draw_axis_line] = draw_axis_line
+      ax[:label_orientation] = label_orientation
+      ax[:ticks] = 0
+      ax[:num_ticks] = 0
+      ax[:tick_labels] = 0
+      ax[:num_tick_labels] = 0
       super(option, ax)
       ax
     end