Glyph cache is cleared by UI_view2d_zoom_cache_reset, when zooming V2D, but is required to calculate text height in UI_view2d_text_cache_draw

This caused text in strips to "jump around"

There was a comment in UI_view2d_zoom_cache_reset:
While scaling we can accumulate fonts at many sizes (~20 or so).
Not an issue with embedded font, but can use over 500Mb with i18n ones! See [#38244].

Reviewed by: Brecht

Differential revision: https://developer.blender.org/D4389

3 files changed, 29 insertions, 11 deletions

diff --git a/source/blender/editors/interface/view2d.c b/source/blender/editors/interface/view2d.c
index 6ac8d83da92..bb49f024bc3 100644
--- a/source/blender/editors/interface/view2d.c
+++ b/source/blender/editors/interface/view2d.c
@@ -2572,6 +2572,8 @@ void UI_view2d_text_cache_draw(ARegion *ar)
 
 	/* investigate using BLF_ascender() */
 	const int font_id = BLF_default();
+
+	BLF_set_default();
 	const float default_height = g_v2d_strings ? BLF_height(font_id, "28", 3) : 0.0f;
 
 	wmOrtho2_region_pixelspace(ar);
diff --git a/source/blender/editors/space_sequencer/sequencer_draw.c b/source/blender/editors/space_sequencer/sequencer_draw.c
index 089a30bcf5e..d37eab0e83d 100644
--- a/source/blender/editors/space_sequencer/sequencer_draw.c
+++ b/source/blender/editors/space_sequencer/sequencer_draw.c
@@ -897,24 +897,26 @@ ImBuf *sequencer_ibuf_get(
 	SeqRenderData context = {0};
 	ImBuf *ibuf;
 	int rectx, recty;
-	float render_size;
-	float proxy_size = 100.0;
 	short is_break = G.is_break;
+	short render_size = sseq->render_size;
+	float proxy_size = 100.0;
+	double scale_fac;
 
-	render_size = sseq->render_size;
 	if (render_size == 0) {
 		render_size = scene->r.size;
+		scale_fac = (float)scene->r.size / 100.0f;
 	}
 	else {
-		proxy_size = render_size;
+		scale_fac = seq_rendersize_to_scale_factor(render_size);
+		proxy_size = scale_fac * 100;
 	}
 
 	if (render_size < 0) {
 		return NULL;
 	}
 
-	rectx = (render_size * (float)scene->r.xsch) / 100.0f + 0.5f;
-	recty = (render_size * (float)scene->r.ysch) / 100.0f + 0.5f;
+	rectx = ((float) scene->r.xsch * scale_fac) + 0.5f;
+	recty = ((float) scene->r.ysch * scale_fac) + 0.5f;
 
 	BKE_sequencer_new_render_data(
 	        bmain, depsgraph, scene,
diff --git a/source/blender/editors/space_sequencer/sequencer_view.c b/source/blender/editors/space_sequencer/sequencer_view.c
index d500a9a081d..962b02aaeb2 100644
--- a/source/blender/editors/space_sequencer/sequencer_view.c
+++ b/source/blender/editors/space_sequencer/sequencer_view.c
@@ -90,7 +90,6 @@ static void sample_apply(bContext *C, wmOperator *op, const wmEvent *event)
 	ARegion *ar = CTX_wm_region(C);
 	ImBuf *ibuf = sequencer_ibuf_get(bmain, depsgraph, scene, sseq, CFRA, 0, NULL);
 	ImageSampleInfo *info = op->customdata;
-	float fx, fy;
 
 	if (ibuf == NULL) {
 		IMB_freeImBuf(ibuf);
@@ -98,18 +97,33 @@ static void sample_apply(bContext *C, wmOperator *op, const wmEvent *event)
 		return;
 	}
 
+	short scene_scale_size = sseq->render_size ? 100 : scene->r.size;
+	float rectx = (float) scene->r.xsch * ((float) scene_scale_size / 100.0f);
+	float recty = (float) scene->r.ysch * ((float) scene_scale_size / 100.0f);
+	float scale_x = (float) ibuf->x / rectx;
+	float scale_y = (float) ibuf->y / recty;
+	float fx, fy;
+
+	/* max coords are +/- (rect* / 2)
+	 */
 	UI_view2d_region_to_view(&ar->v2d, event->mval[0], event->mval[1], &fx, &fy);
 
-	fx += (float) ibuf->x / 2.0f;
-	fy += (float) ibuf->y / 2.0f;
+	fx += rectx / 2.0f;
+	fy += recty / 2.0f;
+
+	/* to get ibuf coords we have to scale by (ibuf->* / rect*)
+	 */
+	fx *= scale_x;
+	fy *= scale_y;
 
 	if (fx >= 0.0f && fy >= 0.0f && fx < ibuf->x && fy < ibuf->y) {
 		const float *fp;
 		unsigned char *cp;
 		int x = (int) fx, y = (int) fy;
 
-		info->x = x;
-		info->y = y;
+		/* we will report mouse position on unscaled image */
+		info->x = 1 + x / scale_x;
+		info->y = 1 + y / scale_y;
 		info->draw = 1;
 		info->channels = ibuf->channels;