Document many more defaults

Including: fallback_resolution, fill_rule, line_cap, line_join,
miter_limit, font_face, font_size, and operator.

src/cairo-surface.c

@@ -887,6 +887,9 @@ slim_hidden_def (cairo_surface_get_device_offset);
  * there is currently no way to have more than one fallback resolution
  * in effect on a single page.
  *
+ * The default fallback resoultion is 300 pixels per inch in both
+ * dimensions.
+ *
  * Since: 1.2
  **/
 void

src/cairo.c

@@ -634,9 +634,7 @@ slim_hidden_def(cairo_pop_group_to_source);
  * operations. See #cairo_operator_t for details on the semantics of
  * each available compositing operator.
  *
- * XXX: I'd also like to direct the reader's attention to some
- * (not-yet-written) section on cairo's imaging model. How would I do
- * that if such a section existed? (cworth).
+ * The default operator is %CAIRO_OPERATOR_OVER.
  **/
 void
 cairo_set_operator (cairo_t *cr, cairo_operator_t op)
@@ -891,6 +889,8 @@ cairo_set_antialias (cairo_t *cr, cairo_antialias_t antialias)
  * (potentially self-intersecting) path. The current fill rule affects
  * both cairo_fill() and cairo_clip(). See #cairo_fill_rule_t for details
  * on the semantics of each available fill rule.
+ *
+ * The default fill rule is %CAIRO_FILL_RULE_WINDING.
  **/
 void
 cairo_set_fill_rule (cairo_t *cr, cairo_fill_rule_t fill_rule)
@@ -959,6 +959,8 @@ cairo_set_line_width (cairo_t *cr, double width)
  * examined by cairo_stroke(), cairo_stroke_extents(), and
  * cairo_stroke_to_path(), but does not have any effect during path
  * construction.
+ *
+ * The default line cap style is %CAIRO_LINE_CAP_BUTT.
  **/
 void
 cairo_set_line_cap (cairo_t *cr, cairo_line_cap_t line_cap)
@@ -976,7 +978,7 @@ cairo_set_line_cap (cairo_t *cr, cairo_line_cap_t line_cap)
 /**
  * cairo_set_line_join:
  * @cr: a cairo context
- * @line_join: a line joint style
+ * @line_join: a line join style
  *
  * Sets the current line join style within the cairo context. See
  * #cairo_line_join_t for details about how the available line join
@@ -986,6 +988,8 @@ cairo_set_line_cap (cairo_t *cr, cairo_line_cap_t line_cap)
  * examined by cairo_stroke(), cairo_stroke_extents(), and
  * cairo_stroke_to_path(), but does not have any effect during path
  * construction.
+ *
+ * The default line join style is %CAIRO_LINE_JOIN_MITER.
  **/
 void
 cairo_set_line_join (cairo_t *cr, cairo_line_join_t line_join)
@@ -1116,6 +1120,15 @@ cairo_get_dash (cairo_t *cr,
  * examined by cairo_stroke(), cairo_stroke_extents(), and
  * cairo_stroke_to_path(), but does not have any effect during path
  * construction.
+ *
+ * The default miter limit value is 10.0, which will convert joins
+ * with interior angles less than 11 degrees to bevels instead of
+ * miters. For reference, a miter limit of 2.0 makes the miter cutoff
+ * at 60 degrees, and a miter limit of 1.414 makes the cutoff at 90
+ * degrees.
+ *
+ * A miter limit for a desired angle can be computed as: miter limit =
+ * 1/sin(angle/2)
  **/
 void
 cairo_set_miter_limit (cairo_t *cr, double limit)
@@ -2598,6 +2611,11 @@ cairo_copy_clip_rectangle_list (cairo_t *cr)
  * It is expected that most applications will need to use a more
  * comprehensive font handling and text layout library, (for example,
  * pango), in conjunction with cairo.
+ *
+ * If text is drawn without a call to cairo_select_font_face(), (nor
+ * cairo_set_font_face() nor cairo_set_scaled_font()), the default
+ * family is "sans", slant is %CAIRO_FONT_SLANT_NORMAL, and weight is
+ * %CAIRO_FONT_WEIGHT_NORMAL.
  **/
 void
 cairo_select_font_face (cairo_t              *cr,
@@ -2712,6 +2730,10 @@ cairo_get_font_face (cairo_t *cr)
  * cairo_set_font_matrix(). This results in a font size of @size user space
  * units. (More precisely, this matrix will result in the font's
  * em-square being a @size by @size square in user space.)
+ *
+ * If text is drawn without a call to cairo_set_font_size(), (nor
+ * cairo_set_font_matrix() nor cairo_set_scaled_font()), the default
+ * font size is 10.0.
  **/
 void
 cairo_set_font_size (cairo_t *cr, double size)

src/cairo.h

@@ -373,6 +373,8 @@ cairo_pop_group_to_source (cairo_t *cr);
  * #cairo_operator_t is used to set the compositing operator for all cairo
  * drawing operations.
  *
+ * The default operator is %CAIRO_OPERATOR_OVER.
+ *
  * The operators marked as <firstterm>unbounded</firstterm> modify their
  * destination even outside of the mask layer (that is, their effect is not
  * bound by the mask layer).  However, their effect can still be limited by
@@ -473,6 +475,8 @@ cairo_set_antialias (cairo_t *cr, cairo_antialias_t antialias);
  * (Note that filling is not actually implemented in this way. This
  * is just a description of the rule that is applied.)
  *
+ * The default fill rule is %CAIRO_FILL_RULE_WINDING.
+ *
  * New entries may be added in future versions.
  **/
 typedef enum _cairo_fill_rule {
@@ -492,7 +496,9 @@ cairo_set_line_width (cairo_t *cr, double width);
  * @CAIRO_LINE_CAP_ROUND: use a round ending, the center of the circle is the end point
  * @CAIRO_LINE_CAP_SQUARE: use squared ending, the center of the square is the end point
  *
- * Specifies how to render the endpoint of a line when stroking.
+ * Specifies how to render the endpoints of the path when stroking.
+ *
+ * The default line cap style is %CAIRO_LINE_CAP_BUTT.
  **/
 typedef enum _cairo_line_cap {
     CAIRO_LINE_CAP_BUTT,
@@ -513,6 +519,8 @@ cairo_set_line_cap (cairo_t *cr, cairo_line_cap_t line_cap);
  * the line width from the joint point
  *
  * Specifies how to render the junction of two lines when stroking.
+ *
+ * The default line join style is %CAIRO_LINE_JOIN_MITER.
  **/
 typedef enum _cairo_line_join {
     CAIRO_LINE_JOIN_MITER,