Cycles: progressive refine option

Just makes progressive refine :)

This means the whole image would be refined gradually using as much
threads as it's set in performance settings. Having enough tiles is
required to have this option working as it's expected.

Technically it's implemented by repeatedly computing next sample for
all the tiles before switching to next sample.

This works around 7-12% slower than regular tile-based rendering, so
use this option only if you really need it.

This commit also fixes progressive update of image when Save Buffers
option is enabled.

And one more thing this commit fixes is handling display buffer with
Save Buffers option enabled. If this option is enabled image buffer
wouldn't have neither byte nor float buffer until image is fully
rendered which could backfire in missing image while rendering in
cases color management cache became full.

This issue solved by allocating byte buffer for image buffer from
tile update callback.

Patch was reviewed by Brecht. He also made some minor edits to
original version to patch. Thanks, man!

6 files changed, 19 insertions, 10 deletions

diff --git a/source/blender/blenkernel/intern/image.c b/source/blender/blenkernel/intern/image.c
index c003a86a0b7..9a1ea15da97 100644
--- a/source/blender/blenkernel/intern/image.c
+++ b/source/blender/blenkernel/intern/image.c
@@ -2617,11 +2617,21 @@ static ImBuf *image_get_render_result(Image *ima, ImageUser *iuser, void **lock_
 	/* free rect buffer if float buffer changes, so it can be recreated with
 	 * the updated result, and also in case we got byte buffer from sequencer,
 	 * so we don't keep reference to freed buffer */
-	if (ibuf->rect_float != rectf || rect || !rectf)
+	if (ibuf->rect_float != rectf || rect)
 		imb_freerectImBuf(ibuf);
 
-	if (rect)
+	if (rect) {
 		ibuf->rect = rect;
+	}
+	else {
+		/* byte buffer of render result has been freed, make sure image buffers
+		 * does not reference to this buffer anymore
+		 * need check for whether byte buffer was allocated and owned by image itself
+		 * or if it's reusing buffer from render result
+		 */
+		if ((ibuf->mall & IB_rect) == 0)
+			ibuf->rect = NULL;
+	}
 
 	if (rectf) {
 		ibuf->rect_float = rectf;
diff --git a/source/blender/compositor/operations/COM_ViewerBaseOperation.cpp b/source/blender/compositor/operations/COM_ViewerBaseOperation.cpp
index d9ca131721f..55a001530ee 100644
--- a/source/blender/compositor/operations/COM_ViewerBaseOperation.cpp
+++ b/source/blender/compositor/operations/COM_ViewerBaseOperation.cpp
@@ -107,7 +107,7 @@ void ViewerBaseOperation:: updateImage(rcti *rect)
 {
 	IMB_partial_display_buffer_update(this->m_ibuf, this->m_outputBuffer, NULL, getWidth(), 0, 0,
 	                                  this->m_viewSettings, this->m_displaySettings,
-	                                  rect->xmin, rect->ymin, rect->xmax, rect->ymax);
+	                                  rect->xmin, rect->ymin, rect->xmax, rect->ymax, FALSE);
 
 	WM_main_add_notifier(NC_WINDOW | ND_DRAW, NULL);
 }
diff --git a/source/blender/editors/render/render_internal.c b/source/blender/editors/render/render_internal.c
index c08ea2b6429..b61280f14ce 100644
--- a/source/blender/editors/render/render_internal.c
+++ b/source/blender/editors/render/render_internal.c
@@ -80,7 +80,6 @@ void image_buffer_rect_update(Scene *scene, RenderResult *rr, ImBuf *ibuf, volat
 	float *rectf = NULL;
 	int ymin, ymax, xmin, xmax;
 	int rymin, rxmin;
-	/* unsigned char *rectc; */  /* UNUSED */
 
 	/* if renrect argument, we only refresh scanlines */
 	if (renrect) {
@@ -143,11 +142,10 @@ void image_buffer_rect_update(Scene *scene, RenderResult *rr, ImBuf *ibuf, volat
 		imb_addrectImBuf(ibuf);
 	
 	rectf += 4 * (rr->rectx * ymin + xmin);
-	/* rectc = (unsigned char *)(ibuf->rect + ibuf->x * rymin + rxmin); */  /* UNUSED */
 
 	IMB_partial_display_buffer_update(ibuf, rectf, NULL, rr->rectx, rxmin, rymin,
 	                                  &scene->view_settings, &scene->display_settings,
-	                                  rxmin, rymin, rxmin + xmax, rymin + ymax);
+	                                  rxmin, rymin, rxmin + xmax, rymin + ymax, TRUE);
 }
 
 /* ****************************** render invoking ***************** */
diff --git a/source/blender/editors/sculpt_paint/paint_image.c b/source/blender/editors/sculpt_paint/paint_image.c
index f60d34428b3..480d4ee6ac1 100644
--- a/source/blender/editors/sculpt_paint/paint_image.c
+++ b/source/blender/editors/sculpt_paint/paint_image.c
@@ -4249,7 +4249,7 @@ static void imapaint_image_update(Scene *scene, SpaceImage *sima, Image *image,
 		IMB_partial_display_buffer_update(ibuf, ibuf->rect_float, (unsigned char *) ibuf->rect, ibuf->x, 0, 0,
 		                                  &scene->view_settings, &scene->display_settings,
 		                                  imapaintpartial.x1, imapaintpartial.y1,
-		                                  imapaintpartial.x2, imapaintpartial.y2);
+		                                  imapaintpartial.x2, imapaintpartial.y2, FALSE);
 	}
 	else {
 		ibuf->userflags |= IB_DISPLAY_BUFFER_INVALID;
diff --git a/source/blender/imbuf/IMB_colormanagement.h b/source/blender/imbuf/IMB_colormanagement.h
index e2604241caf..0653956e113 100644
--- a/source/blender/imbuf/IMB_colormanagement.h
+++ b/source/blender/imbuf/IMB_colormanagement.h
@@ -130,7 +130,8 @@ void IMB_colormanagement_colorspace_items_add(struct EnumPropertyItem **items, i
 void IMB_partial_display_buffer_update(struct ImBuf *ibuf, const float *linear_buffer, const unsigned char *buffer_byte,
                                        int stride, int offset_x, int offset_y, const struct ColorManagedViewSettings *view_settings,
                                        const struct ColorManagedDisplaySettings *display_settings,
-                                       int xmin, int ymin, int xmax, int ymax);
+                                       int xmin, int ymin, int xmax, int ymax,
+                                       int update_orig_byte_buffer);
 
 /* ** Pixel processor functions ** */
 struct ColormanageProcessor *IMB_colormanagement_display_processor_new(const struct ColorManagedViewSettings *view_settings,
diff --git a/source/blender/imbuf/intern/colormanagement.c b/source/blender/imbuf/intern/colormanagement.c
index 37510c10e9a..40b07c02cd7 100644
--- a/source/blender/imbuf/intern/colormanagement.c
+++ b/source/blender/imbuf/intern/colormanagement.c
@@ -2382,9 +2382,9 @@ static void partial_buffer_update_rect(ImBuf *ibuf, unsigned char *display_buffe
 void IMB_partial_display_buffer_update(ImBuf *ibuf, const float *linear_buffer, const unsigned char *byte_buffer,
                                        int stride, int offset_x, int offset_y, const ColorManagedViewSettings *view_settings,
                                        const ColorManagedDisplaySettings *display_settings,
-                                       int xmin, int ymin, int xmax, int ymax)
+                                       int xmin, int ymin, int xmax, int ymax, int update_orig_byte_buffer)
 {
-	if (ibuf->rect && ibuf->rect_float) {
+	if ((ibuf->rect && ibuf->rect_float) || update_orig_byte_buffer)  {
 		/* update byte buffer created by legacy color management */
 
 		unsigned char *rect = (unsigned char *) ibuf->rect;