a pointer to a buffer supplied by the application in which to write contents. This pointer must be suitably aligned for any kind of variable, (for example, a pointer returned by malloc).
the format of pixels in the buffer
the width of the image to be stored in the buffer
the height of the image to be stored in the buffer
the number of bytes between the start of rows in the buffer as allocated. This value should always be computed by formatStrideForWidth before allocating the data buffer.
Creates an image surface for the provided pixel data. The output buffer must be kept around until the Surface is destroyed or Surface.finish() is called on the surface. The initial contents of data will be used as the initial image contents; you must explicitly clear the buffer, using, for example, Context.rectangle() and Context.fill() if you want it cleared.
Note that the stride may be larger than width*bytes_per_pixel to provide proper alignment for each pixel and row. This alignment is required to allow high-performance rendering within cairo. The correct way to obtain a legal stride value is to call formatStrideForWidth with the desired format and maximum image width value, and then use the resulting stride value to allocate the data and to create the image surface. See formatStrideForWidth for example code.