Image editor: Show actual value of single-channel buffer in sample info

Previously if image only had single channel only z buffer value was displaying.
This isn't handy for cases when you've got single channel buffer which is not
a z buffer.

Also fixed possible read past the array.

2 files changed, 41 insertions, 8 deletions

diff --git a/source/blender/editors/space_image/image_draw.c b/source/blender/editors/space_image/image_draw.c
index aff0a4c3d44..e810f4db7dd 100644
--- a/source/blender/editors/space_image/image_draw.c
+++ b/source/blender/editors/space_image/image_draw.c
@@ -197,6 +197,19 @@ void ED_image_draw_info(Scene *scene, ARegion *ar, bool color_manage, bool use_d
 		dx += BLF_width(blf_mono_font, str, sizeof(str));
 	}
 
+	if (channels == 1 && (cp != NULL || fp != NULL)) {
+		if (fp != NULL) {
+			BLI_snprintf(str, sizeof(str), " Val:%-.3f |", fp[0]);
+		}
+		else if (cp != NULL) {
+			BLI_snprintf(str, sizeof(str), " Val:%-.3f |", cp[0] / 255.0f);
+		}
+		glColor3ub(255, 255, 255);
+		BLF_position(blf_mono_font, dx, dy, 0);
+		BLF_draw_ascii(blf_mono_font, str, sizeof(str));
+		dx += BLF_width(blf_mono_font, str, sizeof(str));
+	}
+
 	if (channels >= 3) {
 		glColor3ubv(red);
 		if (fp)
diff --git a/source/blender/editors/space_image/image_ops.c b/source/blender/editors/space_image/image_ops.c
index 88bab733013..8db5a8f9bd3 100644
--- a/source/blender/editors/space_image/image_ops.c
+++ b/source/blender/editors/space_image/image_ops.c
@@ -2826,8 +2826,8 @@ typedef struct ImageSampleInfo {
 	int *zp;
 	float *zfp;
 
-	int draw;
-	int color_manage;
+	bool draw;
+	bool color_manage;
 	int use_default_view;
 } ImageSampleInfo;
 
@@ -2901,7 +2901,7 @@ static void image_sample_apply(bContext *C, wmOperator *op, const wmEvent *event
 
 	if (ibuf == NULL) {
 		ED_space_image_release_buffer(sima, ibuf, lock);
-		info->draw = 0;
+		info->draw = false;
 		return;
 	}
 
@@ -2918,7 +2918,7 @@ static void image_sample_apply(bContext *C, wmOperator *op, const wmEvent *event
 
 		info->x = x;
 		info->y = y;
-		info->draw = 1;
+		info->draw = true;
 		info->channels = ibuf->channels;
 
 		info->colp = NULL;
@@ -2951,10 +2951,24 @@ static void image_sample_apply(bContext *C, wmOperator *op, const wmEvent *event
 		if (ibuf->rect_float) {
 			fp = (ibuf->rect_float + (ibuf->channels) * (y * ibuf->x + x));
 
-			info->colf[0] = fp[0];
-			info->colf[1] = fp[1];
-			info->colf[2] = fp[2];
-			info->colf[3] = fp[3];
+			if (ibuf->channels == 4) {
+				info->colf[0] = fp[0];
+				info->colf[1] = fp[1];
+				info->colf[2] = fp[2];
+				info->colf[3] = fp[3];
+			}
+			else if (ibuf->channels == 3) {
+				info->colf[0] = fp[0];
+				info->colf[1] = fp[1];
+				info->colf[2] = fp[2];
+				info->colf[3] = 1.0f;
+			}
+			else {
+				info->colf[0] = fp[0];
+				info->colf[1] = fp[0];
+				info->colf[2] = fp[0];
+				info->colf[3] = 1.0f;
+			}
 			info->colfp = info->colf;
 
 			copy_v4_v4(info->linearcol, info->colf);
@@ -2965,10 +2979,16 @@ static void image_sample_apply(bContext *C, wmOperator *op, const wmEvent *event
 		if (ibuf->zbuf) {
 			info->z = ibuf->zbuf[y * ibuf->x + x];
 			info->zp = &info->z;
+			if (ibuf->zbuf == (int*)ibuf->rect) {
+				info->colp = NULL;
+			}
 		}
 		if (ibuf->zbuf_float) {
 			info->zf = ibuf->zbuf_float[y * ibuf->x + x];
 			info->zfp = &info->zf;
+			if (ibuf->zbuf_float == ibuf->rect_float) {
+				info->colfp = NULL;
+			}
 		}
 
 		if (curve_mapping && ibuf->channels == 4) {