interior_style(3G)

NAME

interior_style, bf_interior_style − select fill type and boundary visibility for subsequent filled area primitives and back-facing polygons

SYNOPSIS

C Syntax:

void interior_style(fildes,style,edged);
int fildes,style,edged;

void bf_interior_style(fildes,style,edged);
int fildes,style,edged;

FORTRAN77 Syntax:

subroutine interior_style(fildes,style,edged)
integer∗4 fildes,style,edged

subroutine bf_interior_style(fildes,style,edged)
integer∗4 fildes,style,edged

Pascal Syntax:

procedure interior_style(fildes,style,edged:integer);

procedure bf_interior_style(fildes,style,edged:integer);

DESCRIPTION

Input Parameters

fildes Integer file descriptor returned by gopen when an I/O path to a graphics device is opened.

style

INT_HATCH for a hatched interior;

INT_HOLLOW for a hollow interior;

INT_OUTLINE for an outline using the normal fill color calculations;

INT_PATTERN for a user-defined interior fill pattern;

INT_POINT for a point plot using the normal fill color calculations;

INT_SOLID for a solid filled interior;

INT_TEXTURE for a texture filled interior;

edged Set to TRUE (1) if the boundary is to be drawn.
Set to FALSE (0) for no drawn boundary.
The edge is drawn with the current perimeter attributes (for back-facing polygons: the current back-facing perimeter color.

Discussion

The interior_style call specifies whether to draw edges for, or fill the interior of, certain output primitives (i.e. those that form an enclosed area). Applicable primitives include: arc, circle, ellipse, polygon, quadrilateral_mesh, rectangle, and triangular_strip.

Hollow style areas are not filled. Solid style areas are filled with the current fill_color or bf_fill_color.

INT_OUTLINE
style areas are drawn by outlining the fill area’s border using all of the normal fill color calculations, including light sourcing and shading, if supported by the device driver. Lines are generated at the intersections of the fill area with any of the current clip limits. This interior style can be used to generate light sourced, shaded wireframe images.

INT_POINT
style areas are drawn as a point plot of the fill area’s vertices using all of the normal fill color calculations, including light sourcing and shading, if supported by the device driver. Points are generated at the intersections of the fill area with any of the current clip limits.

Polygons

Hatched polygons are filled in the current fill color with the hatch attributes defined by hatch_type , hatch_spacing , and hatch_orientation . When hatching is enabled, polygons are replaced by a set of vectors, either parallel or crossing. For this reason, several features normally associated with polygons are not supported when hatching is selected. These include hidden surface removal, lighting models, shading, depth cueing, back-face cull, and back-face control.

Setting edged equal to TRUE(1) displays a boundary of the current perimeter_color, and will obscure INT_OUTLINE or INT_POINT.

User-defined patterns are specified through the pattern_define call.

The perimeter_type and perimeter_repeat_length routines set the type and repeat length for front-facing polygon edges.

Back-facing polygons

Back-facing polygons use the specified interior style when bf_control has been called with the attr parameter set to TRUE(1).

INT_PATTERN and INT_HATCH interior styles are not supported for back-facing polygons.

Setting edged equal to TRUE(1) displays a boundary of the current bf_perimeter_color, and will obscure INT_OUTLINE or INT_POINT.

The bf_perimeter_type and bf_perimeter_repeat_length routines set the type and repeat length for back-facing polygon edges.

DEFAULTS

INT_SOLID, not edged.

Museum

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