Name
hw_RawPolyFill -- draw filled polygon to pixel buffer (V7.1)
Synopsis
void hw_RawPolyFill(APTR dst, struct hwVertex *v, int n, ULONG color,
         ULONG flags, struct hwTagList *tags);
Function
This function can be used to draw a filled polygon to a raw pixel buffer. Note that this function does not draw to a Hollywood bitmap but to a raw pixel buffer only. This makes it possible to use hw_RawPolyFill() in lots of different contexts. If you want to use hw_RawPolyFill() on a Hollywood bitmap, you need to lock the bitmap first using hw_LockBitMap() and then pass the raw pixel buffer pointer obtained by hw_LockBitMap() to hw_RawPolyFill().

You have to pass an array of vertices defining the polygon in the v parameter. The n parameter specifies how many vertices there are in n. struct hwVertex looks like this:

 
struct hwVertex
{
    int X;
    int Y;
};

Note that before hw_RawPolyFill() starts drawing, the polygon vertices will be normalized. Thus, it is also possible to use negative coordinates in v. The destination bitmap must be large enough to store the polygon The following tags are recognized by hw_RawPolyFill():

HWRPFTAG_PIXFMT:
This tag can be used to set the pixel format hw_RawPolyFill() should use when drawing into the pixel buffer. You have to pass a pixel format constant in the iData member of this tag. See Pixel format information for details. This tag defaults to HWOS_PIXFMT_ARGB32.

HWRPFTAG_DSTWIDTH:
This tag must be specified. You have to pass the number of pixels per row in the destination buffer in the iData member of this tag. If you don't pass this tag, hw_RawPolyFill() won't work.

HWRPFTAG_X:
This tag allows you to specify the destination x offset for the polygon. Note that the destination offset can't be in the vertices themselves since hw_RawPolyFill() will always normalize the vertices before drawing. (V9.1)

HWRPFTAG_Y:
This tag allows you to specify the destination y offset for the polygon. Note that the destination offset can't be in the vertices themselves since hw_RawPolyFill() will always normalize the vertices before drawing. (V9.1)

Additionally, hw_RawPolyFill() supports the following flags:

HWRPFFLAGS_BLEND:
If this flag is set, then hw_RawPolyFill() will draw a polygon with alpha-blending to the destination pixel buffer. The blend intensity is taken from the upper 8 bits in the color parameter that you've passed to hw_RawPolyFill(). If this flag is not set, then hw_RawPolyFill() will just draw with a static color.

Note that this function does not do any clipping. You must make sure that the destination raw pixel buffer is large enough.

Designer compatibility
Unsupported

Inputs
dst
pointer to destination raw pixel buffer
v
array containing the vertices to draw
n
number of vertices in array
color
ARGB color to use; the A component is only used if HWRPFFLAGS_BLEND has been set
flags
additional drawing flags (see above)
tags
additional drawing tags (see above)

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