LinearGradientBrush::TranslateTransform method (gdiplusbrush.h)

Article
10/13/2021

The LinearGradientBrush::TranslateTransform method updates this brush's current transformation matrix with the product of itself and a translation matrix.

Syntax

Status TranslateTransform(
  [in] REAL        dx,
  [in] REAL        dy,
  [in] MatrixOrder order
);

Parameters

[in] dx

Type: REAL

Real number that specifies the horizontal component of the translation.

[in] dy

Type: REAL

Real number that specifies the vertical component of the translation.

[in] order

Type: MatrixOrder

Optional. Element of the MatrixOrder enumeration that specifies the order of the multiplication. MatrixOrderPrepend specifies that the translation matrix is on the left, and MatrixOrderAppend specifies that the translation matrix is on the right. The default value is MatrixOrderPrepend.

Return value

Type: Status

If the method succeeds, it returns Ok, which is an element of the Status enumeration.

If the method fails, it returns one of the other elements of the Status enumeration.

Remarks

A single 3 ×3 matrix can store any sequence of affine transformations. If you have several 3 ×3 matrices, each of which represents an affine transformation, the product of those matrices is a single 3 ×3 matrix that represents the entire sequence of transformations. The transformation represented by that product is called a composite transformation. For example, suppose matrix S represents a scaling, and matrix T represents a translation. If matrix M is the product ST, then matrix M represents a composite transformation: first scale, then translate.

The order of matrix multiplication is important. In general, the matrix product RT is not the same as the matrix product TR. In the example given in the previous paragraph, the composite transformation represented by RT (first rotate, then translate) is not the same as the composite transformation represented by TR (first translate, then rotate).

Examples

The following example creates a linear gradient brush and uses it to fill a rectangle. Next, the code modifies the brush's transformation matrix, applying a composite transformation, and then fills a rectangle with the transformed brush.

VOID Example_TranslateTrans(HDC hdc)
{
   Graphics myGraphics(hdc);

   LinearGradientBrush linGrBrush(
      Rect(0, 0, 80, 40),
      Color(255, 255, 0, 0),  // red
      Color(255, 0, 0, 255),  // blue
      LinearGradientModeHorizontal);

   // Fill a large area with the linear gradient brush (no transformation).
   myGraphics.FillRectangle(&linGrBrush, 0, 0, 800, 150);

   // Apply a composite transformation: first scale, then translate.
   linGrBrush.ScaleTransform(2, 1);                     // horizontal doubling
   linGrBrush.TranslateTransform(30, MatrixOrderAppend);// translation

   // Fill a large area with the transformed linear gradient brush.
   myGraphics.FillRectangle(&linGrBrush, 0, 200, 800, 150);
}

Requirements

Requirement	Value
Minimum supported client	Windows XP, Windows 2000 Professional [desktop apps only]
Minimum supported server	Windows 2000 Server [desktop apps only]
Target Platform	Windows
Header	gdiplusbrush.h (include Gdiplus.h)
Library	Gdiplus.lib
DLL	Gdiplus.dll

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