diff --git a/eat.el b/eat.el
index c84be77..cbd806c 100644
--- a/eat.el
+++ b/eat.el
@@ -176,7 +176,19 @@ t Fallback to plain Eshell if `stty' is not available.
FUNCTION Call FUNCTION with the command and arguments (using
`apply') and fallback to plain Eshell if it returns
nil."
- :type 'boolean
+ :type '(radio (const :tag "Do nothing" nil)
+ (const :tag "Fallback to plain Eshell" t)
+ (const :tag "Ask interactively" ask)
+ (function :tag "Function"))
+ :group 'eat-eshell)
+
+(defcustom eat-sixel-render-formats '(svg half-block background none)
+ "List of formats to render Sixel, in order of preference."
+ :type '(repeat (choice (const :tag "SVG Image" svg)
+ (const :tag "UTF-8 half block" half-block)
+ (const :tag "Background color" background)
+ (const :tag "None" none)))
+ :group 'eat-ui
:group 'eat-eshell)
(defcustom eat-semi-char-non-bound-keys
@@ -1112,12 +1124,12 @@ Nil when not in alternative display mode.")
(copy-sequence (make-vector 256 nil))
:documentation "Sixel color registers.")
(sixel-color 0 :documentation "Current Sixel color register.")
- (sixel-display-method
+ (sixel-render-format
'background
- :documentation "Method to display renders Sixel image.")
+ :documentation "Format to render Sixel images in.")
(sixel-image-height
nil
- :documentation "Height of images used to display Sixels.")
+ :documentation "Height of images used to display Sixel.")
(sixel-scroll-mode t :documentation "Whether to auto-scroll.")
(sixel-initial-cursor-pos
'(1 . 1)
@@ -3004,7 +3016,8 @@ If NULLIFY is non-nil, nullify flushed part of Sixel buffer."
(cl-incf i)
(cl-incf j))
(pcase-exhaustive
- (eat--t-term-sixel-display-method eat--t-term)
+ (eat--t-term-sixel-render-format eat--t-term)
+ ('none)
('background
(when-let* ((color (aref (aref bitmap 0) 0)))
(put-text-property (point) (1+ (point)) 'face
@@ -3965,11 +3978,11 @@ If NULLIFY is non-nil, nullify flushed part of Sixel buffer."
(signal 'wrong-type-argument (list 'consp value)))
(setf (eat--t-term-char-width terminal) (car value))
(setf (eat--t-term-char-height terminal) (cdr value)))
- ('sixel-display-method
- (unless (memq value '(background half-block svg))
- (error "`sixel-display-method' parameter must be set to one of\
+ ('sixel-render-format
+ (unless (memq value '(background half-block svg none))
+ (error "`sixel-render-format' parameter must be set to one of\
the supported methods"))
- (setf (eat--t-term-sixel-display-method terminal) value))
+ (setf (eat--t-term-sixel-render-format terminal) value))
('sixel-image-height
(setf (eat--t-term-sixel-image-height terminal) value)))
;; Set the parameter.
@@ -5024,6 +5037,20 @@ selection, or nil if none."
"Ring the bell."
(ding t))
+(defun eat--sixel-render-format ()
+ "Return the suitable Sixel render format."
+ (cl-block nil
+ (dolist (fmt eat-sixel-render-formats)
+ (pcase-exhaustive fmt
+ ('none (cl-return 'none))
+ ('background (cl-return 'background))
+ ('half-block (when (char-displayable-p ?▄)
+ (cl-return 'half-block)))
+ ('svg (when (and (display-graphic-p)
+ (image-type-available-p 'svg))
+ (cl-return 'svg)))))
+ 'none))
+
(defun eat--set-cwd (_ host cwd)
"Set CWD as the current working directory (`default-directory').
@@ -6606,12 +6633,8 @@ same Eat buffer. The hook `eat-exec-hook' is run after each exec."
(setf (eat-term-set-cwd-function eat--terminal) #'eat--set-cwd)
(setf (eat-term-parameter eat--terminal 'ui-command-function)
#'eat--handle-uic)
- (setf (eat-term-parameter eat--terminal 'sixel-display-method)
- (cond ((and (display-graphic-p)
- (image-type-available-p 'svg))
- 'svg)
- ((char-displayable-p ?▄) 'half-block)
- (t 'background)))
+ (setf (eat-term-parameter eat--terminal 'sixel-render-format)
+ (eat--sixel-render-format))
(when (display-graphic-p)
(setf (eat-term-parameter eat--terminal 'sixel-image-height)
(cons (/ (float (default-font-height))
@@ -6984,12 +7007,8 @@ PROGRAM can be a shell command."
(setf (eat-term-set-cwd-function eat--terminal) #'eat--set-cwd)
(setf (eat-term-parameter eat--terminal 'ui-command-function)
#'eat--eshell-handle-uic)
- (setf (eat-term-parameter eat--terminal 'sixel-display-method)
- (cond ((and (display-graphic-p)
- (image-type-available-p 'svg))
- 'svg)
- ((char-displayable-p ?▄) 'half-block)
- (t 'background)))
+ (setf (eat-term-parameter eat--terminal 'sixel-render-format)
+ (eat--sixel-render-format))
(when (display-graphic-p)
(setf (eat-term-parameter eat--terminal 'sixel-image-height)
(cons (/ (float (default-font-height))
diff --git a/eat.texi b/eat.texi
index bfe36d9..212948b 100644
--- a/eat.texi
+++ b/eat.texi
@@ -908,6 +908,28 @@ and @var{n} can be any number between 0 and 9 (inclusive). For
example, the font 6 is can be changed by customizing
@code{eat-term-font-6}. Font 0 is the default font.
+@node Sixel
+@cindex sixel
+@chapter Sixel
+
+Eat can show Sixel graphics. Sixel is a bitmap graphics format that
+can be used to display graphics in a terminal, for example, images, or
+plotting graphs.
+
+Eat converts Sixel graphics to an image format Emacs can natively
+display. This preference of image formats can be configured by
+customizing the @code{eat-sixel-render-formats} user option.
+
+@vindex eat-sixel-render-formats
+@defopt eat-sixel-render-formats
+List of formats to render Sixel, in order of preference. Each element
+of the list is one of @code{svg}, @code{half-block},
+@code{background}, @code{none}. @code{svg} means to use SVG image
+format, @code{half-block} means to use UTF-8 half block characters,
+@code{background} means to just use background color, and @code{none}
+means to not render the image, instead just clear the area.
+@end defopt
+
@node Blinking Text
@cindex blinking text
@cindex text, blinking