[PATCH 39/52] expo: Support object alignment
Simon Glass
sjg at chromium.org
Wed Mar 19 15:54:44 CET 2025
Add support for left, right and centred alignment for text, in the
horizontal dimension.
Also support top, bottom and centred in the vertical dimension, for the
text object as a whole.
Alignment is not yet implemented for images. It has no meaning for
menus. A textline object uses a text object internally, so alignment
is supported there.
Provide some documentation to explain how objects are positioned.
Signed-off-by: Simon Glass <sjg at chromium.org>
---
boot/scene.c | 104 +++++++++++++++++++++++++++++++++++++++++--
doc/develop/expo.rst | 31 +++++++++++++
include/expo.h | 63 ++++++++++++++++++++++++++
test/boot/expo.c | 23 ++++++++--
4 files changed, 214 insertions(+), 7 deletions(-)
diff --git a/boot/scene.c b/boot/scene.c
index 640d972ce8f..4f9d4a44e2b 100644
--- a/boot/scene.c
+++ b/boot/scene.c
@@ -305,6 +305,30 @@ int scene_obj_set_bbox(struct scene *scn, uint id, int x0, int y0, int x1,
return 0;
}
+int scene_obj_set_halign(struct scene *scn, uint id, enum scene_obj_align aln)
+{
+ struct scene_obj *obj;
+
+ obj = scene_obj_find(scn, id, SCENEOBJT_NONE);
+ if (!obj)
+ return log_msg_ret("osh", -ENOENT);
+ obj->horiz = aln;
+
+ return 0;
+}
+
+int scene_obj_set_valign(struct scene *scn, uint id, enum scene_obj_align aln)
+{
+ struct scene_obj *obj;
+
+ obj = scene_obj_find(scn, id, SCENEOBJT_NONE);
+ if (!obj)
+ return log_msg_ret("osv", -ENOENT);
+ obj->vert = aln;
+
+ return 0;
+}
+
int scene_obj_set_hide(struct scene *scn, uint id, bool hide)
{
int ret;
@@ -330,6 +354,44 @@ int scene_obj_flag_clrset(struct scene *scn, uint id, uint clr, uint set)
return 0;
}
+static void handle_alignment(enum scene_obj_align horiz,
+ enum scene_obj_align vert,
+ struct scene_obj_bbox *bbox,
+ struct scene_obj_dims *dims,
+ int xsize, int ysize,
+ struct scene_obj_offset *offset)
+{
+ int width, height;
+
+ width = bbox->x1 - bbox->x0;
+ height = bbox->y1 - bbox->y0;
+
+ switch (horiz) {
+ case SCENEOA_CENTRE:
+ offset->xofs = (width - dims->x) / 2;
+ break;
+ case SCENEOA_RIGHT:
+ offset->xofs = width - dims->x;
+ break;
+ case SCENEOA_LEFT:
+ offset->xofs = 0;
+ break;
+ }
+
+ switch (vert) {
+ case SCENEOA_CENTRE:
+ offset->yofs = (height - dims->y) / 2;
+ break;
+ case SCENEOA_BOTTOM:
+ offset->yofs = height - dims->y;
+ break;
+ case SCENEOA_TOP:
+ default:
+ offset->yofs = 0;
+ break;
+ }
+}
+
int scene_obj_get_hw(struct scene *scn, uint id, int *widthp)
{
struct scene_obj *obj;
@@ -444,10 +506,12 @@ static int scene_txt_render(struct expo *exp, struct udevice *dev,
struct scene_txt_generic *gen, int x, int y,
int menu_inset)
{
- const struct vidconsole_mline *mline;
+ const struct vidconsole_mline *mline, *last;
struct video_priv *vid_priv;
struct vidconsole_colour old;
enum colour_idx fore, back;
+ struct scene_obj_dims dims;
+ struct scene_obj_bbox bbox;
const char *str;
int ret;
@@ -481,9 +545,28 @@ static int scene_txt_render(struct expo *exp, struct udevice *dev,
obj->bbox.y1, vid_priv->colour_bg);
}
+ mline = alist_get(&gen->lines, 0, typeof(*mline));
+ last = alist_get(&gen->lines, gen->lines.count - 1, typeof(*mline));
+ if (mline)
+ dims.y = last->bbox.y1 - mline->bbox.y0;
+ bbox.y0 = obj->bbox.y0;
+ bbox.y1 = obj->bbox.y1;
+
alist_for_each(mline, &gen->lines) {
- vidconsole_set_cursor_pos(cons, x + mline->bbox.x0,
- y + mline->bbox.y0);
+ struct scene_obj_offset offset;
+
+ bbox.x0 = obj->bbox.x0;
+ bbox.x1 = obj->bbox.x1;
+ dims.x = mline->bbox.x1 - mline->bbox.x0;
+ handle_alignment(obj->horiz, obj->vert, &bbox, &dims,
+ obj->bbox.x1 - obj->bbox.x0,
+ obj->bbox.y1 - obj->bbox.y0, &offset);
+
+ x = obj->bbox.x0 + offset.xofs;
+ y = obj->bbox.y0 + offset.yofs + mline->bbox.y0;
+ if (y > bbox.y1)
+ break; /* clip this line and any following */
+ vidconsole_set_cursor_pos(cons, x, y);
vidconsole_put_stringn(cons, str + mline->start, mline->len);
}
if (obj->flags & SCENEOF_POINT)
@@ -510,7 +593,7 @@ static int scene_obj_render(struct scene_obj *obj, bool text_mode)
int x, y, ret;
y = obj->bbox.y0;
- x = obj->bbox.x0;
+ x = obj->bbox.x0 + obj->ofs.xofs;
vid_priv = dev_get_uclass_priv(dev);
switch (obj->type) {
@@ -621,14 +704,27 @@ int scene_calc_arrange(struct scene *scn, struct expo_arrange_info *arr)
int scene_arrange(struct scene *scn)
{
struct expo_arrange_info arr;
+ int xsize = 0, ysize = 0;
struct scene_obj *obj;
+ struct udevice *dev;
int ret;
+ dev = scn->expo->display;
+ if (dev) {
+ struct video_priv *priv = dev_get_uclass_priv(dev);
+
+ xsize = priv->xsize;
+ ysize = priv->ysize;
+ }
+
ret = scene_calc_arrange(scn, &arr);
if (ret < 0)
return log_msg_ret("arr", ret);
list_for_each_entry(obj, &scn->obj_head, sibling) {
+ handle_alignment(obj->horiz, obj->vert, &obj->bbox, &obj->dims,
+ xsize, ysize, &obj->ofs);
+
switch (obj->type) {
case SCENEOBJT_NONE:
case SCENEOBJT_IMAGE:
diff --git a/doc/develop/expo.rst b/doc/develop/expo.rst
index 8f63ccbe3ef..d6fc487e030 100644
--- a/doc/develop/expo.rst
+++ b/doc/develop/expo.rst
@@ -107,6 +107,37 @@ refer to objects which have been created. So a menu item is just a collection
of IDs of text and image objects. When adding a menu item you must create these
objects first, then create the menu item, passing in the relevant IDs.
+Position and alignment
+~~~~~~~~~~~~~~~~~~~~~~
+
+Objects are typically positioned automatically, when scene_arrange() is called.
+However it is possible to position objects manually. The scene_obj_set_pos()
+sets the coordinates of the top left of the object.
+
+All objects have a bounding box. Typically this is calculated by looking at the
+object contents, in `scene_calc_arrange()`. The calculated dimensions of each
+object are stored in the object's `dims` field.
+
+It is possible to adjust the size of an object with `scene_obj_set_size()` or
+even set the bounding box, with `scene_obj_set_bbox()`. The `SCENEOF_SIZE_VALID`
+flag tracks whether the width/height should be maintained when the position
+changes.
+
+If the bounding box is larger than the object needs, the object can be aligned
+to different edges within the box. Objects can be left- or right-aligned,
+or centred. For text objects this applies to each line of text. Normally objects
+are drawn starting at the top of their bounding box, but they can be aligned
+vertically to the bottom, or centred vertically within the box.
+
+Where the width of a text object's bounding box is smaller than the space needed
+to show the next, the text is word-wrapped onto multiple lines, assuming there
+is enough vertical space. Newline characters in the next cause a new line to be
+started. The measurement information is created by the Truetype console driver
+and stored in an alist in `struct scene_txt_generic`.
+
+When the object is drawn the `ofs` field indicates the x and y offset to use,
+from the top left of the bounding box. These values are affected by alignment.
+
Creating an expo
----------------
diff --git a/include/expo.h b/include/expo.h
index 8833dcceb7e..001f7db2553 100644
--- a/include/expo.h
+++ b/include/expo.h
@@ -210,6 +210,19 @@ struct scene_obj_bbox {
int y1;
};
+/**
+ * struct scene_obj_offset - Offsets for drawing the object
+ *
+ * Stores the offset from x0, x1 at which objects are drawn
+ *
+ * @xofs: x offset
+ * @yofs: y offset
+ */
+struct scene_obj_offset {
+ int xofs;
+ int yofs;
+};
+
/**
* struct scene_obj_dims - Dimensions of the object being drawn
*
@@ -225,6 +238,30 @@ struct scene_obj_dims {
int y;
};
+/**
+ * enum scene_obj_halign - Horizontal alignment of objects
+ *
+ * Objects are normally drawn on the left size of their bounding box. This
+ * properly allows aligning on the right or having the object centred.
+ *
+ * @SCENEOA_LEFT: Left of object is aligned with its x coordinate
+ * @SCENEOA_RIGHT: Right of object is aligned with x + w
+ * @SCENEOA_CENTRE: Centre of object is aligned with centre of bounding box
+ * @SCENEOA_TOP: Left of object is aligned with its x coordinate
+ * @SCENEOA_BOTTOM: Right of object is aligned with x + w
+ *
+ * Note: It would be nice to make this a char type but Sphinx riddles:
+ * ./include/expo.h:258: error: Cannot parse enum!
+ * enum scene_obj_align : char {
+ */
+enum scene_obj_align {
+ SCENEOA_LEFT,
+ SCENEOA_RIGHT,
+ SCENEOA_CENTRE,
+ SCENEOA_TOP = SCENEOA_LEFT,
+ SCENEOA_BOTTOM = SCENEOA_RIGHT,
+};
+
/**
* enum scene_obj_flags_t - flags for objects
*
@@ -255,7 +292,10 @@ enum {
* @id: ID number of the object
* @type: Type of this object
* @bbox: Bounding box for this object
+ * @ofs: Offset from x0, y0 where the object is drawn
* @dims: Dimensions of the text/image (may be smaller than bbox)
+ * @horiz: Horizonal alignment
+ * @vert: Vertical alignment
* @flags: Flags for this object
* @bit_length: Number of bits used for this object in CMOS RAM
* @start_bit: Start bit to use for this object in CMOS RAM
@@ -267,7 +307,10 @@ struct scene_obj {
uint id;
enum scene_obj_t type;
struct scene_obj_bbox bbox;
+ struct scene_obj_offset ofs;
struct scene_obj_dims dims;
+ enum scene_obj_align horiz;
+ enum scene_obj_align vert;
u8 flags;
u8 bit_length;
u16 start_bit;
@@ -755,6 +798,26 @@ int scene_obj_set_width(struct scene *scn, uint id, int w);
int scene_obj_set_bbox(struct scene *scn, uint id, int x0, int y0, int x1,
int y1);
+/**
+ * scene_obj_set_halign() - Set the horizontal alignment of an object
+ *
+ * @scn: Scene to update
+ * @id: ID of object to update
+ * @aln: Horizontal alignment to use
+ * Returns: 0 if OK, -ENOENT if @id is invalid
+ */
+int scene_obj_set_halign(struct scene *scn, uint id, enum scene_obj_align aln);
+
+/**
+ * scene_obj_set_valign() - Set the vertical alignment of an object
+ *
+ * @scn: Scene to update
+ * @id: ID of object to update
+ * @aln: Vertical alignment to use
+ * Returns: 0 if OK, -ENOENT if @id is invalid
+ */
+int scene_obj_set_valign(struct scene *scn, uint id, enum scene_obj_align aln);
+
/**
* scene_obj_set_hide() - Set whether an object is hidden
*
diff --git a/test/boot/expo.c b/test/boot/expo.c
index c76051e1c7d..7bea189da04 100644
--- a/test/boot/expo.c
+++ b/test/boot/expo.c
@@ -492,13 +492,14 @@ static int expo_render_image(struct unit_test_state *uts)
60));
ut_assertok(scene_obj_set_pos(scn, OBJ_TEXT2, 200, 600));
+ /* this string is clipped as it extends beyond its bottom bound */
id = scene_txt_str(scn, "text", OBJ_TEXT3, STR_TEXT3,
- "this is yet\nanother string, with word-wrap",
+ "this is yet\nanother string, with word-wrap and it goes on for quite a while",
NULL);
ut_assert(id > 0);
ut_assertok(scene_txt_set_font(scn, OBJ_TEXT3, "nimbus_sans_l_regular",
60));
- ut_assertok(scene_obj_set_bbox(scn, OBJ_TEXT3, 500, 200, 1000, 700));
+ ut_assertok(scene_obj_set_bbox(scn, OBJ_TEXT3, 500, 200, 1000, 350));
id = scene_menu(scn, "main", OBJ_MENU, &menu);
ut_assert(id > 0);
@@ -666,9 +667,25 @@ static int expo_render_image(struct unit_test_state *uts)
ut_assertok(scene_arrange(scn));
ut_assertok(expo_render(exp));
- ut_asserteq(15016, video_compress_fb(uts, dev, false));
+ ut_asserteq(16450, video_compress_fb(uts, dev, false));
ut_assertok(video_check_copy_fb(uts, dev));
+ /* do some alignment checks */
+ ut_assertok(scene_obj_set_halign(scn, OBJ_TEXT3, SCENEOA_CENTRE));
+ ut_assertok(expo_render(exp));
+ ut_asserteq(16438, video_compress_fb(uts, dev, false));
+ ut_assertok(scene_obj_set_halign(scn, OBJ_TEXT3, SCENEOA_RIGHT));
+ ut_assertok(expo_render(exp));
+ ut_asserteq(16449, video_compress_fb(uts, dev, false));
+
+ ut_assertok(scene_obj_set_halign(scn, OBJ_TEXT3, SCENEOA_LEFT));
+ ut_assertok(scene_obj_set_valign(scn, OBJ_TEXT3, SCENEOA_CENTRE));
+ ut_assertok(expo_render(exp));
+ ut_asserteq(18909, video_compress_fb(uts, dev, false));
+ ut_assertok(scene_obj_set_valign(scn, OBJ_TEXT3, SCENEOA_BOTTOM));
+ ut_assertok(expo_render(exp));
+ ut_asserteq(18839, video_compress_fb(uts, dev, false));
+
/* make sure only the preview for the second item is shown */
obj = scene_obj_find(scn, ITEM1_PREVIEW, SCENEOBJT_NONE);
ut_asserteq(true, obj->flags & SCENEOF_HIDE);
--
2.43.0
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