Ticket #8618: dragable-colorwell.patch

src/preferences/appearance/ColorWell.cpp

@@ -7 +7 @@
  */
 #include "ColorWell.h"
 
+#include <new>
+#include <stdio.h>
+
+#include <Bitmap.h>
+
+
+#define DRAG_INIT_DIST 10.0
+
+
 ColorWell::ColorWell(BRect frame, BMessage *msg, uint32 resizingMode, uint32 flags)
- :  BView(frame,"ColorWell", resizingMode, flags | B_WILL_DRAW)
+ :  BView(frame,"ColorWell", resizingMode, flags | B_WILL_DRAW),
+    fTrackingStart(-1.0, -1.0)
 {
     SetViewColor(B_TRANSPARENT_COLOR);
     SetLowColor(0,0,0);
@@ -139 +149 @@
 {
     is_rect=is_rectangle;
 }
+
+void
+ColorWell::MouseDown(BPoint where)
+{
+    if (Bounds().Contains(where))
+        fTrackingStart = where;
+}
+
+void
+ColorWell::MouseUp(BPoint where)
+{
+    fTrackingStart.x = -1.0;
+    fTrackingStart.y = -1.0;
+}
+
+void
+ColorWell::MouseMoved(BPoint where, uint32 transit,
+    const BMessage* dragMessage)
+{
+    if (Bounds().Contains(fTrackingStart)) {
+        if (point_point_distance(where, fTrackingStart) > DRAG_INIT_DIST
+            || transit == B_EXITED_VIEW) {
+            _DragColor();
+            fTrackingStart.x = -1.0;
+            fTrackingStart.y = -1.0;
+        }
+    }
+}
+
+void
+ColorWell::_DragColor()
+{
+    BBitmap* bitmap = new(std::nothrow) BBitmap(BRect(0.0, 0.0, 15.0, 15.0),
+        B_RGB32);
+
+    BMessage message = make_color_drop_message(currentcol, bitmap);
+
+    DragMessage(&message, bitmap, B_OP_ALPHA, BPoint(9.0, 9.0));
+}
+
+BMessage
+make_color_drop_message(rgb_color color, BBitmap* bitmap)
+{
+    // prepare message
+    BMessage message(B_PASTE);
+    char hexString[8];
+    snprintf(hexString, sizeof(hexString), "#%.2X%.2X%.2X",
+        color.red, color.green, color.blue);
+    message.AddData("text/plain", B_MIME_TYPE, &hexString, sizeof(hexString));
+    message.AddData("RGBColor", B_RGB_COLOR_TYPE, &color, sizeof(color));
+    // prepare bitmap
+    if (bitmap && bitmap->IsValid()
+        && (bitmap->ColorSpace() == B_RGB32
+            || bitmap->ColorSpace() == B_RGBA32)) {
+        uint8* bits = (uint8*)bitmap->Bits();
+        uint32 bpr = bitmap->BytesPerRow();
+        uint32 width = bitmap->Bounds().IntegerWidth() + 1;
+        uint32 height = bitmap->Bounds().IntegerHeight() + 1;
+        for (uint32 y = 0; y < height; y++) {
+            uint8* bitsHandle = bits;
+            for (uint32 x = 0; x < width; x++) {
+                if (x == 0 || y == 0 ) {
+                    // top or left border
+                    bitsHandle[0] = (uint8)min_c(255, color.blue * 1.2 + 40);
+                    bitsHandle[1] = (uint8)min_c(255, color.green * 1.2 + 40);
+                    bitsHandle[2] = (uint8)min_c(255, color.red * 1.2 + 40);
+                    bitsHandle[3] = 180;
+                } else if ((x == width - 2 || y == height - 2)
+                           && !(x == width - 1 || y == height - 1)) {
+                    // bottom or right border
+                    bitsHandle[0] = (uint8)(color.blue * 0.8);
+                    bitsHandle[1] = (uint8)(color.green * 0.8);
+                    bitsHandle[2] = (uint8)(color.red * 0.8);
+                    bitsHandle[3] = 180;
+                } else if (x == width - 1 || y == height - 1) {
+                    // shadow
+                    bitsHandle[0] = 0;
+                    bitsHandle[1] = 0;
+                    bitsHandle[2] = 0;
+                    bitsHandle[3] = 100;
+                } else {
+                    // color
+                    bitsHandle[0] = color.blue;
+                    bitsHandle[1] = color.green;
+                    bitsHandle[2] = color.red;
+                    bitsHandle[3] = 180;
+                }
+                if ((x == 0 && y == height - 1) || (y == 0 && x == width - 1)) {
+                    // spare pixels of shadow
+                    bitsHandle[0] = 0;
+                    bitsHandle[1] = 0;
+                    bitsHandle[2] = 0;
+                    bitsHandle[3] = 50;
+                }
+                bitsHandle += 4;
+            }
+            bits += bpr;
+        }
+    }
+    return message;
+}
+

src/preferences/appearance/ColorWell.h

@@ -27 +27 @@
     virtual void SetTarget(BHandler *tgt);
     virtual void SetEnabled(bool value);
     void SetMode(bool is_rectangle);
+    virtual void MouseDown(BPoint where);
+    virtual void MouseUp(BPoint where);
+    virtual void MouseMoved(BPoint where, uint32 transit,
+                              const BMessage* dragMessage);
 protected:
     BInvoker *invoker;  
     bool is_enabled, is_rect;
     rgb_color disabledcol, currentcol;
+private:
+    void _DragColor();
+    BPoint fTrackingStart;
 };
 
+
+// point_point_distance
+inline float
+point_point_distance(BPoint a, BPoint b)
+{
+    float xDiff = b.x - a.x;
+    float yDiff = b.y - a.y;
+    return sqrtf(xDiff * xDiff + yDiff * yDiff);
+}
+
+
+BMessage make_color_drop_message(rgb_color color, BBitmap* bitmap);
+
+
 #endif