An Android Game Development Framework - Beginning Android Games - page 224

if (bitmap.getConfig() == Config. RGB_565 )
format=PixmapFormat. RGB565 ;
else if (bitmap.getConfig() == Config. ARGB_4444 )
format=PixmapFormat. ARGB4444 ;
else
format=PixmapFormat. ARGB8888 ;
return new AndroidPixmap(bitmap, format);
}
The newPixmap() method tries to load a Bitmap from an asset file, using the specified
PixmapFormat . We start by translating the PixmapFormat into one of the constants of the Android
Config class used in Chapter 4. Next, we create a new Options instance and set our preferred
color format. Then, we try to load the Bitmap from the asset via the BitmapFactory , and throw a
RuntimeException if something goes wrong. Otherwise, we check what format the BitmapFactory
used to load the Bitmap and translate it into a PixmapFormat enumeration value. Remember
that the BitmapFactory might decide to ignore our desired color format, so we have to check to
determine what it used to decode the image. Finally, we construct a new AndroidBitmap instance
based on the Bitmap we loaded, as well as its PixmapFormat , and return it to the caller.
public void clear( int color) {
canvas.drawRGB((color & 0xff0000) >>16, (color & 0xff00) >>8,
(color & 0xff));
}
The clear() method extracts the red, green, and blue components of the specified 32-bit ARGB
color parameter and calls the Canvas.drawRGB() method, which clears our artificial framebuffer
with that color. This method ignores any alpha value of the specified color, so we don't have to
extract it.
public void drawPixel(int x, int y, int color) {
paint.setColor(color);
canvas.drawPoint(x, y, paint);
}
The drawPixel() method draws a pixel of our artificial framebuffer via the Canvas.drawPoint()
method. First, we set the color of our Paint member variable and pass it to the drawing method
in addition to the x and y coordinates of the pixel.
public void drawLine( int x, int y, int x2, int y2, int color) {
paint.setColor(color);
canvas.drawLine(x, y, x2, y2, paint);
}
The drawLine() method draws the given line of the artificial framebuffer, using the Paint member
to specify the color when calling the Canvas.drawLine() method.
public void drawRect( int x, int y, int width, int height, int color) {
paint.setColor(color);
paint.setStyle(Style. FILL );
canvas.drawRect(x, y, x+width - 1, y+width - 1, paint);
}