[[ CanvasTextImageBounds ]] Implement image bounds on Windows

livecodeian · livecodeian · commit ee45aa1c9b82 · 2015-03-05T15:32:58.000Z
diff --git a/libgraphics/src/w32text.cpp b/libgraphics/src/w32text.cpp
@@ -712,3 +712,106 @@ void MCGPlatformFinalize(void)
 }
 
 ////////////////////////////////////////////////////////////////////////////////
+
+static void __expand_bounds(RECT& r, POINT& p)
+{
+    if (p . x < r . left)
+        r . left = p . x;
+    if (p . x > r . right)
+        r . right = p . x;
+    if (p . y < r . top)
+        r . top = p . y;
+    if (p . y > r . bottom)
+        r . bottom = p . y;
+}
+
+bool MCGContextMeasurePlatformTextImageBounds(MCGContextRef self, const unichar_t *p_text, uindex_t p_length, const MCGFont& p_font, const MCGAffineTransform& p_transform, MCGRectangle &r_bounds)
+{
+    bool t_success;
+    t_success = true;
+
+    if (t_success)
+        t_success = SelectObject(s_measure_dc, p_font . fid) != NULL;
+
+    if (t_success)
+    {
+        XFORM t_xform;
+        t_xform . eM11 = p_transform . a;
+        t_xform . eM12 = 0;
+        t_xform . eM21 = 0;
+        t_xform . eM22 = p_transform . d;
+        t_xform . eDx = 0;
+        t_xform . eDy = 0;
+        t_success = SetWorldTransform(s_measure_dc, &t_xform);
+    }
+
+    if (t_success)
+    {
+        BeginPath(s_measure_dc);
+        SetBkMode(s_measure_dc, TRANSPARENT);
+        SetTextAlign(s_measure_dc, TA_BASELINE);
+        if (p_font . fixed_advance == 0)
+            TextOutW(s_measure_dc, 0, 0, p_text, p_length / 2);
+        else
+        {
+            // MW-2013-12-05: [[ Bug 11535 ]] If fixed advance, then make the advance
+            //   width of each char fixed_advance.
+            INT *t_dxs;
+            /* UNCHECKED */ MCMemoryNewArray(p_length / 2, t_dxs);
+            for(uindex_t i = 0; i < p_length / 2; i++)
+                t_dxs[i] = p_font . fixed_advance;
+            ExtTextOutW(s_measure_dc, 0, 0, 0, NULL, p_text, p_length / 2, t_dxs);
+            MCMemoryDeleteArray(t_dxs);
+        }
+        EndPath(s_measure_dc);
+
+        int t_count;
+        t_count = GetPath(s_measure_dc, NULL, NULL, 0);
+
+        RECT t_bounds;
+        t_bounds . left = INT_MAX;
+        t_bounds . top = INT_MAX;
+        t_bounds . right = INT_MIN;
+        t_bounds . bottom = INT_MIN;
+
+        POINT *t_points;
+        BYTE *t_types;
+        t_points = new POINT[t_count];
+        t_types = new BYTE[t_count];
+        GetPath(s_measure_dc, t_points, t_types, t_count);
+
+        for(int i = 0; i < t_count;)
+        {
+            switch(t_types[i] & ~PT_CLOSEFIGURE)
+            {
+                case PT_MOVETO:
+                    __expand_bounds(t_bounds, t_points[i]);
+                    i += 1;
+                    break;
+
+                case PT_LINETO:
+                    __expand_bounds(t_bounds, t_points[i]);
+                    i += 1;
+                    break;
+
+                case PT_BEZIERTO:
+                    __expand_bounds(t_bounds, t_points[i + 0]);
+                    __expand_bounds(t_bounds, t_points[i + 1]);
+                    __expand_bounds(t_bounds, t_points[i + 2]);
+                    i += 3;
+                    break;
+            }
+        }
+
+        delete t_points;
+        delete t_types;
+
+		r_bounds = MCGRectangleMake(t_bounds.left, t_bounds.top, t_bounds.right - t_bounds.left, t_bounds.bottom - t_bounds.top);
+    }
+
+    AbortPath(s_measure_dc);
+
+    return true;
+}
+
+////////////////////////////////////////////////////////////////////////////////
