[PATCH 06/52] video: truetype: Support newlines in the measured string

[Simon Glass]

It is useful to be able to embed newline characters in the string and
have the text measured into multiple lines. Add support for this.

Signed-off-by: Simon Glass <sjg at chromium.org>
---

 drivers/video/console_truetype.c | 25 ++++++++++++++++++++++++-
 include/video_console.h          |  4 ++++
 test/dm/video.c                  | 26 ++++++++++++++++++++------
 3 files changed, 48 insertions(+), 7 deletions(-)

diff --git a/drivers/video/console_truetype.c b/drivers/video/console_truetype.c
index 39d77ad9818..6eca5d7f543 100644
--- a/drivers/video/console_truetype.c
+++ b/drivers/video/console_truetype.c
@@ -771,10 +771,33 @@ static int truetype_measure(struct udevice *dev, const char *name, uint size,
 			neww += stbtt_GetCodepointKernAdvance(font, lastch, ch);
 		lastch = ch;
 
+		/* see if we need to start a new line */
+		if (ch == '\n') {
+			mline.bbox.x0 = 0;
+			mline.bbox.y0 = bbox->y1;
+			mline.bbox.x1 = tt_ceil((double)width * met->scale);
+			bbox->y1 += met->font_size;
+			mline.bbox.y1 = bbox->y1;
+			mline.bbox.valid = true;
+			mline.start = start;
+			mline.len = (s - text) - start;
+			if (lines && !alist_add(lines, mline))
+				return log_msg_ret("ttm", -ENOMEM);
+			log_debug("line x1 %d y0 %d y1 %d start %d len %d text '%.*s'\n",
+				  mline.bbox.x1, mline.bbox.y0, mline.bbox.y1,
+				  mline.start, mline.len, mline.len, text + mline.start);
+
+			start = s - text;
+			if (ch == '\n')
+				start++;
+			lastch = 0;
+			neww = 0;
+		}
+
 		width = neww;
 	}
 
-	/* add the line */
+	/* add the final line */
 	mline.bbox.x0 = 0;
 	mline.bbox.y0 = bbox->y1;
 	mline.bbox.x1 = tt_ceil((double)width * met->scale);
diff --git a/include/video_console.h b/include/video_console.h
index ee9ce3c0e37..a0ee9ab62e9 100644
--- a/include/video_console.h
+++ b/include/video_console.h
@@ -244,6 +244,8 @@ struct vidconsole_ops {
 	/**
 	 * measure() - Measure the bounding box of some text
 	 *
+	 * The text can include newlines
+	 *
 	 * @dev:	Console device to use
 	 * @name:	Font name to use (NULL to use default)
 	 * @size:	Font size to use (0 to use default)
@@ -342,6 +344,8 @@ int vidconsole_select_font(struct udevice *dev, const char *name, uint size);
 /**
  * vidconsole_measure() - Measure the bounding box of some text
  *
+ * The text can include newlines
+ *
  * @dev:	Device to adjust
  * @name:	Font name to use (NULL to use default)
  * @size:	Font size to use (0 to use default)
diff --git a/test/dm/video.c b/test/dm/video.c
index d3fd74a9a9a..a3f3b046882 100644
--- a/test/dm/video.c
+++ b/test/dm/video.c
@@ -781,7 +781,7 @@ DM_TEST(dm_test_video_damage, UTF_SCAN_PDATA | UTF_SCAN_FDT);
 /* Test font measurement */
 static int dm_test_font_measure(struct unit_test_state *uts)
 {
-	const char *test_string = "There is always much to be said for not "
+	const char *test_string = "There is always much\nto be said for not "
 		"attempting more than you can do and for making a certainty of "
 		"what you try. But this principle, like others in life and "
 		"war, has its exceptions.";
@@ -790,6 +790,7 @@ static int dm_test_font_measure(struct unit_test_state *uts)
 	struct video_priv *priv;
 	struct udevice *dev, *con;
 	struct alist lines;
+	int nl;
 
 	ut_assertok(uclass_get_device(UCLASS_VIDEO, 0, &dev));
 	priv = dev_get_uclass_priv(dev);
@@ -804,18 +805,31 @@ static int dm_test_font_measure(struct unit_test_state *uts)
 				       &lines));
 	ut_asserteq(0, bbox.x0);
 	ut_asserteq(0, bbox.y0);
-	ut_asserteq(0x47a, bbox.x1);
-	ut_asserteq(0x12, bbox.y1);
-	ut_asserteq(1, lines.count);
+	ut_asserteq(0x3ea, bbox.x1);
+	ut_asserteq(0x24, bbox.y1);
+	ut_asserteq(2, lines.count);
+
+	nl = strchr(test_string, '\n') - test_string;
 
 	line = alist_get(&lines, 0, struct vidconsole_mline);
 	ut_assertnonnull(line);
 	ut_asserteq(0, line->bbox.x0);
 	ut_asserteq(0, line->bbox.y0);
-	ut_asserteq(0x47a, line->bbox.x1);
+	ut_asserteq(0x8c, line->bbox.x1);
 	ut_asserteq(0x12, line->bbox.y1);
 	ut_asserteq(0, line->start);
-	ut_asserteq(strlen(test_string), line->len);
+	ut_asserteq(20, line->len);
+	ut_asserteq(nl, line->len);
+
+	line++;
+	ut_asserteq(0x0, line->bbox.x0);
+	ut_asserteq(0x12, line->bbox.y0);
+	ut_asserteq(0x3ea, line->bbox.x1);
+	ut_asserteq(0x24, line->bbox.y1);
+	ut_asserteq(21, line->start);
+	ut_asserteq(nl + 1, line->start);
+	ut_asserteq(163, line->len);
+	ut_asserteq(strlen(test_string + nl + 1), line->len);
 
 	return 0;
 }
-- 
2.43.0