image histogram/sample line couldn't show HDR colors. now allow zooming the view to see colors up to 10.0

2 files changed, 16 insertions, 4 deletions

diff --git a/source/blender/editors/interface/interface_draw.c b/source/blender/editors/interface/interface_draw.c
index 1d88838ecc5..d8eb1b011bd 100644
--- a/source/blender/editors/interface/interface_draw.c
+++ b/source/blender/editors/interface/interface_draw.c
@@ -714,6 +714,8 @@ static void histogram_draw_one(float r, float g, float b, float alpha,
 	}
 }
 
+#define HISTOGRAM_TOT_GRID_LINES 4
+
 void ui_draw_but_HISTOGRAM(ARegion *ar, uiBut *but, uiWidgetColors *UNUSED(wcol), rcti *recti)
 {
 	Histogram *hist = (Histogram *)but->poin;
@@ -749,9 +751,16 @@ void ui_draw_but_HISTOGRAM(ARegion *ar, uiBut *but, uiWidgetColors *UNUSED(wcol)
 
 	glColor4f(1.f, 1.f, 1.f, 0.08f);
 	/* draw grid lines here */
-	for (i = 1; i < 4; i++) {
-		fdrawline(rect.xmin, rect.ymin + (i / 4.f) * h, rect.xmax, rect.ymin + (i / 4.f) * h);
-		fdrawline(rect.xmin + (i / 4.f) * w, rect.ymin, rect.xmin + (i / 4.f) * w, rect.ymax);
+	for (i = 1; i < (HISTOGRAM_TOT_GRID_LINES + 1); i++) {
+		const float fac = (float)i / (float)HISTOGRAM_TOT_GRID_LINES;
+
+		/* so we can tell the 1.0 color point */
+		if (i == HISTOGRAM_TOT_GRID_LINES) {
+			glColor4f(1.0f, 1.0f, 1.0f, 0.5f);
+		}
+
+		fdrawline(rect.xmin, rect.ymin + fac * h, rect.xmax, rect.ymin + fac * h);
+		fdrawline(rect.xmin + fac * w, rect.ymin, rect.xmin + fac * w, rect.ymax);
 	}
 	
 	if (hist->mode == HISTO_MODE_LUMA) {
@@ -773,6 +782,8 @@ void ui_draw_but_HISTOGRAM(ARegion *ar, uiBut *but, uiWidgetColors *UNUSED(wcol)
 	draw_scope_end(&rect, scissor);
 }
 
+#undef HISTOGRAM_TOT_GRID_LINES
+
 void ui_draw_but_WAVEFORM(ARegion *ar, uiBut *but, uiWidgetColors *UNUSED(wcol), rcti *recti)
 {
 	Scopes *scopes = (Scopes *)but->poin;
diff --git a/source/blender/editors/interface/interface_handlers.c b/source/blender/editors/interface/interface_handlers.c
index 32aef5d3939..15202760315 100644
--- a/source/blender/editors/interface/interface_handlers.c
+++ b/source/blender/editors/interface/interface_handlers.c
@@ -3872,7 +3872,8 @@ static int ui_numedit_but_HISTOGRAM(uiBut *but, uiHandleButtonData *data, int mx
 		const float yfac = minf(powf(hist->ymax, 2.0f), 1.0f) * 0.5f;
 		hist->ymax += dy * yfac;
 	
-		CLAMP(hist->ymax, 1.f, 100.f);
+		/* 0.1 allows us to see HDR colors up to 10 */
+		CLAMP(hist->ymax, 0.1f, 100.f);
 	}
 	
 	data->draglastx = mx;