Work-around strange codegen problem with x0 in Bargraph.onDraw

One less problem in #35

gui/dplug/gui/drawex.d

@@ -157,4 +157,52 @@ if (isWritableView!V && isNumeric!T && is(COLOR : ViewColor!V))
             }
         }
     }
+}
+
+void aaFillRectFloat(bool CHECKED=true, V, COLOR)(auto ref V v, float x1, float y1, float x2, float y2, COLOR color) 
+    if (isWritableView!V && is(COLOR : ViewColor!V))
+{
+    import ae.utils.math;
+    sort2(x1, x2);
+    sort2(y1, y2);
+
+    int ix1 = cast(int)(floor(x1));
+    int iy1 = cast(int)(floor(y1));
+    int ix2 = cast(int)(floor(x2));
+    int iy2 = cast(int)(floor(y2));
+    float fx1 = x1 - ix1;
+    float fy1 = y1 - iy1;
+    float fx2 = x2 - ix2;
+    float fy2 = y2 - iy2;
+
+    static ubyte toAlpha(float fraction) pure nothrow @nogc
+    {
+        return cast(ubyte)(cast(int)(0.5f + 255.0f * fraction));
+    }
+
+    v.aaPutPixelFloat!CHECKED(ix1, iy1, color, toAlpha( (1-fx1) * (1-fy1) ));
+    v.hline!CHECKED(ix1+1, ix2, iy1, color, toAlpha(1 - fy1));
+    v.aaPutPixelFloat!CHECKED(ix2, iy1, color, toAlpha( fx2 * (1-fy1) ));
+
+    v.vline!CHECKED(ix1, iy1+1, iy2, color, toAlpha(1 - fx1));
+    v.vline!CHECKED(ix2, iy1+1, iy2, color, toAlpha(fx2));
+
+    v.aaPutPixelFloat!CHECKED(ix1, iy2, color, toAlpha( (1-fx1) * fy2 ));
+    v.hline!CHECKED(ix1+1, ix2, iy2, color,  toAlpha(fy2));
+    v.aaPutPixelFloat!CHECKED(ix2, iy2, color, toAlpha( fx2 * fy2 ));
+
+    v.fillRect!CHECKED(ix1+1, iy1+1, ix2, iy2, color);
+}
+
+template aaPutPixelFloat(bool CHECKED=true)
+{
+    void aaPutPixelFloat(V, COLOR)(auto ref V v, int x, int y, COLOR color, ubyte alpha)
+    {
+        static if (CHECKED)
+            if (x<0 || x>=v.w || y<0 || y>=v.h)
+                return;
+
+        COLOR* p = v.pixelPtr(x, y);
+        *p = COLOR.op!q{.blend(a, b, c)}(color, *p, alpha);
+    }
 }

gui/dplug/gui/toolkit/bargraph.d

@@ -68,34 +68,34 @@ public:
 
         box2f available = box2f(border, border, width - border, height - border);
 
-        float heightPerLed = available.height / cast(float)numLeds;
-        float widthPerLed = available.width / cast(float)numChannels;
+        float heightPerLed = cast(float)(available.height) / cast(float)numLeds;
+        float widthPerLed = cast(float)(available.width) / cast(float)numChannels;
 
         float tolerance = 1.0f / numLeds;
 
         foreach(channel; 0..numChannels)
         {
             float value = getValue(channel);
+            float x0 = border + widthPerLed * (channel + 0.15f);
+            float x1 = x0 + widthPerLed * 0.7f;
+
             foreach(i; 0..numLeds)
             {
-                float x0 = available.min.x + widthPerLed * (channel + 0.15f);
-                float x1 = x0 + widthPerLed * 0.7f;
-                float y0 = available.min.y + heightPerLed * (i + 0.1f);
+                float y0 = border + heightPerLed * (i + 0.1f);
                 float y1 = y0 + heightPerLed * 0.8f;
 
-                depthMap.aaFillRect(x0, y0, x1, y1, RGBA(60, 255, 0, 0));
+                depthMap.aaFillRectFloat!true(x0, y0, x1, y1, RGBA(60, 255, 0, 0));
 
                 float ratio = 1 - i / cast(float)(numLeds - 1);
 
-
                 ubyte shininess = cast(ubyte)(0.5f + 255.0f * (1 - smoothStep(value - tolerance, value, ratio)));
 
                 RGBA color = _leds[i].diffuse;
                 color.r = (color.r * (255 + shininess) + 255) / 510;
                 color.g = (color.g * (255 + shininess) + 255) / 510;
                 color.b = (color.b * (255 + shininess) + 255) / 510;
                 color.a = shininess;
-                diffuseMap.aaFillRect(x0, y0, x1, y1, color);
+                diffuseMap.aaFillRectFloat!true(x0, y0, x1, y1, color);
 
             }
         }