Graphics Primitives : Subroutine Descriptions

Group GG : General Graphics

IGrGetPixel Get a screen pixel value as a 24-bit value
IGrInit Re-initialise graphics output
IGrSelect Select target drawing surface (window/bitmap/field/metafile)

Group GA : Graphics Area/Units

IGrArea Define size of graphics area
IGrAreaClear Clear the current graphics screen area
IGrUnits Define plotting units to be used
IGrUnitsFromPixelsConvert to user-unit co-ordinate from a pixel co-ord
IGrUnitsRotate Rotate the co-ordinate system by 0/90/180/270 degrees
IGrUnitsToPixels Convert from user-unit co-ordinate to a pixel co-ord
IGrViewport Define size of graphics viewport

Group GS : Graphics Style Selection

IGrColour Select graphics colour using a colour name
IGrColourModelSelect 8-bit or 24-bit colour model
IGrColourN Select graphics colour using a colour number
IGrFillPatternDefine fill pattern (solid/stippled/hatched)
IGrLineCap Select line cap style (butt, round, projecting square)
IGrLineJoin Select line join style (mitre, round, bevel)
IGrLineType Select line type (solid, dots, dashes, etc.)
IGrLineWidth Set line width
IGrPalette Redefine colour palette
IGrPaletteInitRe-initialise palette
IGrPlotMode Select plotting mode (normal/and/or/exclusive-or)

Group GD : Graphics Drawing/Movement Primitives

IGrArc Draw/fill circular arc at an absolute position
IGrArcRel Draw/fill circular arc at the current position
IGrArrow Draw an arrow pointing to a specified position
IGrArrowJoin Draw an arrow joining two points
IGrBlockCopy Bit block copy
IGrBlockMove Bit block move
IGrBorder Draw border around current graphics area
IGrCircle Draw/fill circle at an absolute position
IGrCircleRel Draw/fill circle at the current position
IGrEllipse Draw/fill an ellipse at an absolute position
IGrEllipseRel Draw/fill an ellipse at the current position
IGrJoin Draw line between two absolute plotting positions
IGrJoinRel Draw line from absolute position to a relative pos
IGrLineTo Draw line to a new absolute position
IGrLineToRel Draw line to a new relative position
IGrMarker Draw predefined marker at an absolute position
IGrMarkerRel Draw predefined marker at the current position
IGrMoveTo Move current plotting position to a new absolute pos
IGrMoveToRel Move current plotting position to a new relative pos
IGrParallel Draw/fill parallelogram given absolute co-ordinates
IGrParallelRel Draw/fill parallelogram given height & width
IGrPoint Draw a single point at new absolute position
IGrPointRel Draw a single point at new relative position
IGrPolygonComplexDraw/fill a complex (possibly intersecting) polygon
IGrPolygonGrad Fill a horizontally/vertically graduated polygon
IGrPolygonShaded Fill a shaded polygon, RGB value specified for each vertex
IGrPolygonSimple Draw/fill a simple non-intersecting polygon
IGrPolyLine Draw a polyline through a set of absolute co-ordinates
IGrRectangle Draw/fill rectangle given absolute co-ordinates
IGrRectangleRel Draw/fill rectangle given height & width
IGrTrapezium Draw/fill trapezium given absolute co-ordinates
IGrTrapeziumRel Draw/fill trapezium given height & width
IGrTriangle Draw/fill triangle given absolute co-ordinates
IGrTriangleRel Draw/fill triangle given two relative co-ordinates
WGrBezier Draw a Bezier curve
WGrBezierPoints Calculate and return the points of a Bezier curve
WGrBSpline Draw a cubic B-Spline curve
WGrBSplinePoints Calculate and return the points of a cubic B-Spline curve
WGrCurve Draw a curve which passes through all the supplied points
WGrCurvePoints Calculate and return the points of a coincident curve

Group GP : Graphics Proximity Checks

IGrDistanceLine Measure distance from a point to a line
IGrInsideCircle Is a given point inside a given circle?
IGrInsideEllipseIs a given point inside a given ellipse?
IGrInsidePolygonIs a given point inside a given polygon?
IGrIntersectLineCalculate point at which two lines intersect

Click here to return to Subroutine Library page.