I have to draw an image on surface on windows application built in Visual Studio 2005.
The image is of type .png and it contains a transparent background.
When I create a bitmap with the image and draw on the window (in onPaint Event), the image loses its transparency background and transperancy part of image turns into white colour. How can I retain the transparency?
Call this on the bitmap object, replacing "Color tranparentColor" with the color you want to be transparent:
myBitmap->MakeTransparent(Color transparentColor);
If you want the upper left pixel of the bmp to be the transparent color, you would do this:
// Get the color of a background pixel.
Color backColor = myBitmap->GetPixel( 1, 1 );
// Make backColor transparent for myBitmap.
myBitmap->MakeTransparent( backColor );
Related
Using properties of "label" not able to set the backcolor as transparent ... when i select the color transparent from the option which is showing some color as backcolor, if transparent works properly must show background instead of some colors. please help
If you add a control at design time when setting the background to transparent it 'displays' the background of the form not the control on which it was placed unless that control is a container such as a panel.
2 options:
1 place the label on a panel and the label then displays the panel background (which can be a picture if that is what you are trying to do)
2 place the label programatically i.e.
dim Label1 As New Label
Control.Controls.Add(Label1)
Label1.BackColor = Color.Transparent
I am creating program with multileyered picturebox, the image of picturebox is update dynamically from bitmap in memory, and i want to clear the selected part on bitmap to transparent color so i can see image of picturebox behind it.
Here is my code
Dim gBmp As Graphics = Graphics.FromImage(GraphLayer(LayerArray))
Dim TileSrcCrop As New Rectangle(nVal(xTile), nVal(yTile), TileSize, TileSize)
Dim TileDrawSize As New Rectangle(nVal(H), nVal(V), TileSize, TileSize)
gBmp.DrawImage(GraphImage(LayerArray), TileDrawSize, TileSrcCrop, GraphicsUnit.Pixel)
PicMap(LayerArray).Image = GraphLayer(LayerArray)
Thanks
What I'm about to say may only be for Windows icons, but IIRC, the top left pixel must be assigned the color that you want to designate as the color for transparency. You'll usually see MS use Magenta (255, 0, 255). This is called a transparency mask. Then, anywhere you want the color to be transparent, you use the color you placed in the top left pixel.
HTH -- and let me know if it's only for icons, but I think it's for Windows bitmap files, too.
I have Button image with Rounded Button image. I am tiling image to get bigger button in QML . I am using parent as rectangle and image as BorderImage. After tiling I am getting rectangle on top image is visible. I need to remove the part of the rectangle so that only rounded button image (Has transparency) is Visible. Even i need to change the color of the behind rectangle so that Color animation is possible.
Please suggest efficient method to remove the behind rectangle and provide the color animation also.
I am attaching the Rounded button border image as attachment and source code for tiling the button image.
Rectangle{
id:outerBorderRect
smooth:true
anchors.fill:parent
//opacity:.25
//border.width:0
BorderImage{
id:innerBorderRect
smooth:true
anchors.fill:parent
border{left:20;top:16;right:17;bottom:20}
horizontalTileMode:BorderImage.Round
verticalTileMode:BorderImage.Round
source:"button_3.png"
}
}
A simple and semi-hack way to do this is to use the radius property in Rectangle to hide the corners of your button.
Or you could use a proper mask by using Qt's OpacityMask.
I'm not sure what kind of animation you're looking for. You'll have to provide more details for me to answer that part.
I'm trying to find a way to mark the border of a QGraphicsScene, and make it resizable inside a QGraphicsView, to create something similar to Microsoft Paint.
In other words, my current QGraphicsView looks like this:
But my image is only this big, as indicated by the red box:
I want my QGraphicsView to be like this (the little black boxes are cornergrabbers for resizing the canvas):
Functionally, I want it to be similar to MS Paint:
The canvas (scene) is resizable, and the scrollbars on the window (view) appear when needed. The blue background color (solid gray background) appears behind the canvas.
How would I go about accomplishing this?
To try to get the grey background, I've been experimenting with QGraphicsView.setBackgroundBrush() and QGraphicsScene.setBackgroundBrush(). I've learned that QGraphicsView's background brush completely overrides QGraphicsScene's background brush if one is set. Even if I only set the background brush for QGraphicsScene, that background brush extends over the image's original boundaries.
Here is a link to my test code.
Help is appreciated!
I have to struggle with your constructors...dunno if it works on Windows, but have to make it to work with Linux. Try :
def setPixmap(self, pixmap):
if self.pixmap_item:
self.removeItem(self.pixmap_item)
self.pixmap_item = self.addPixmap(pixmap)
self.setPixBackGround()
def setPixBackGround(self):
# put Background rect for image
pixR = self.pixmap_item.pixmap().rect()
bgRectangle = self.addRect(pixR.x()-10, pixR.y()-10,
pixR.width()+20, pixR.height()+20)
# set color and Z value to put it behind image
bgColor = QColor(58, 176, 176)
bgRectangle.setBrush(bgColor)
bgRectangle.setZValue(-.1)
# take coordinates for brabbers
bgR = bgRectangle.rect()
grab1R = QRect(-5,-5,10,10)
# put grabbers as wish...
grab1 = self.addRect(grab1R)
grab1.setPos(bgR.topLeft())
grab2 = self.addRect(grab1R)
grab2.setPos(bgR.topRight())
# ....etc....
I have drawn one rectangle by using RectangleFigure in draw2d. And I am able to
color the rectangle figure by calling rectangleFigure.setBackgroundColor.
Now the same way I want to color the Image also. For that I used ImageFigure in
draw2d and I gave the background color by calling ImageFigure.setBackgroundColor().
But it does not give any color for me. So How can I give the background color
to the image figure in draw2d?
RectangleFigure extends Shape which draws it's own background by default. ImageFigure directly extends Figure which will only draw the background if you set it as Opaque:
imageFigure.setOpaque(true);