Grease Pencil selection order is wrong #62101

New Issue

William Reynish · 2019-03-01T21:59:33+01:00

William Reynish commented

2019-03-01 21:59:33 +01:00

System Information
Operating system: macOS 10.14.3
Graphics card: AMD Radeon R9 M395X 4096 MB

Blender Version
Broken: Blender 2.80 beta, 2019-03-01

Short description of error
Grease Pencil selection order is wrong. Grease Pencil objects will always be selected last, even if they are in front.

Exact steps for others to reproduce the error
In the blend file below, there's a simple example of a bunch of GP objects in front of a mesh:

Click over the Grease Pencil monkey objects to select them. Rather than the GP objects being selected, the mesh object behind them will be selected instead.

GP_selection_order_bug.blend

**System Information** Operating system: macOS 10.14.3 Graphics card: AMD Radeon R9 M395X 4096 MB **Blender Version** Broken: Blender 2.80 beta, 2019-03-01 **Short description of error** Grease Pencil selection order is wrong. Grease Pencil objects will always be selected last, even if they are in front. **Exact steps for others to reproduce the error** In the blend file below, there's a simple example of a bunch of GP objects in front of a mesh: ![Screenshot 2019-03-01 at 21.55.27.png](https://archive.blender.org/developer/F6738247/Screenshot_2019-03-01_at_21.55.27.png) Click over the Grease Pencil monkey objects to select them. Rather than the GP objects being selected, the mesh object behind them will be selected instead. [GP_selection_order_bug.blend](https://archive.blender.org/developer/F6738251/GP_selection_order_bug.blend)

William Reynish commented

2019-03-01 21:59:33 +01:00

Added subscriber: @WilliamReynish

Antonio Vazquez was assigned by William Reynish

2019-03-01 22:01:46 +01:00

Antonio Vazquez commented

2019-03-01 23:26:05 +01:00

Added subscriber: @fclem

Antonio Vazquez commented

2019-03-01 23:26:05 +01:00

We need @fclem help here.

I only add the render section for select, but I did not make any code of the selection itself. No idea why is working in this way.

We need @fclem help here. I only add the render section for select, but I did not make any code of the selection itself. No idea why is working in this way.

Antonio Vazquez was unassigned by William Reynish

2019-03-01 23:37:45 +01:00

Clément Foucault was assigned by William Reynish

2019-03-01 23:37:45 +01:00

William Reynish commented

2019-03-01 23:37:45 +01:00

Added subscriber: @antoniov

Germano Cavalcante commented

2019-07-04 18:11:42 +02:00

Added subscriber: @mano-wii

Germano Cavalcante commented

2019-07-04 18:11:42 +02:00

Is this bug still reproducible in the latest builds?

Germano Cavalcante commented

2019-07-05 01:24:53 +02:00

I tried again by disabling the OpenGL Depth Picking option and I was able to reproduce the bug.

The problem is that gpencil calls gpencil_free_runtime_data(stl) inside GPENCIL_draw_scene() thus releasing some resources in the first call from DRW_draw_select_loop(...).
However, DRW_draw_select_loop(...) calls drw_engines_draw_scene() at least three consecutive times.
I don't know if the solution has to be done in the DRW_manager itself or in the GPencil engine.

I also noticed an efficiency issue.
gpu_select_query_load_id(id) is called several times consecutively for the same id.
This forces the creation and use of more glQueries.
It would be good to investigate this too.

I tried again by disabling the `OpenGL Depth Picking` option and I was able to reproduce the bug. The problem is that gpencil calls `gpencil_free_runtime_data(stl)` inside `GPENCIL_draw_scene()` thus releasing some resources in the first call from `DRW_draw_select_loop(...)`. However, `DRW_draw_select_loop(...)` calls `drw_engines_draw_scene()` at least three consecutive times. I don't know if the solution has to be done in the `DRW_manager` itself or in the `GPencil engine`. I also noticed an efficiency issue. `gpu_select_query_load_id(id)` is called several times consecutively for the same `id`. This forces the creation and use of more `glQueries`. It would be good to investigate this too.

Clément Foucault commented

2019-07-05 15:03:46 +02:00

This forces the creation and use of more glQueries.

If I remember correctly, Similar queries are merged together.

However, DRW_draw_select_loop(...) calls drw_engines_draw_scene() at least three consecutive times.

Best way of fixing it would be to introduce a post draw callback in the draw engine struct and free the runtime data here. But that maybe a bit too big of a modification at this time.

Other possible fix is to move all these resources to a per layer storage (DRW_view_layer_engine_data_get) and discard only in cache_init.

>This forces the creation and use of more glQueries. If I remember correctly, Similar queries are merged together. >However, DRW_draw_select_loop(...) calls drw_engines_draw_scene() at least three consecutive times. Best way of fixing it would be to introduce a post draw callback in the draw engine struct and free the runtime data here. But that maybe a bit too big of a modification at this time. Other possible fix is to move all these resources to a per layer storage (DRW_view_layer_engine_data_get) and discard only in cache_init.

Germano Cavalcante commented

2019-07-05 16:07:11 +02:00

Is there any way to recreate the entire runtime_data within GPENCIL_draw_scene(...)?
It would be another possible fix.

Is there any way to recreate the entire runtime_data within `GPENCIL_draw_scene(...)`? It would be another possible fix.

Antonio Vazquez commented

2019-07-05 16:38:12 +02:00

I think this can be complex...you have a list of object sorted by z-depth, the layers, the strokes with different types, etc...not sure what really you need, but maybe could be possible if you give me more details of what you want to do.

Have you checked drw_gpencil_select_render(stl, psl); function?

I think this can be complex...you have a list of object sorted by z-depth, the layers, the strokes with different types, etc...not sure what really you need, but maybe could be possible if you give me more details of what you want to do. Have you checked `drw_gpencil_select_render(stl, psl);` function?

Germano Cavalcante commented

2019-07-05 17:15:24 +02:00

@antoniov would be nice to remove that gpencil_free_runtime_data(stl) from GPENCIL_draw_scene(...).
At least for selection.

@antoniov would be nice to remove that `gpencil_free_runtime_data(stl)` from `GPENCIL_draw_scene(...)`. At least for selection.

blender-admin commented

2019-07-05 23:11:53 +02:00

This issue was referenced by a0f3ea7da3

This issue was referenced by a0f3ea7da3f65333fbac9c2d528c4242c417860d

Clément Foucault was unassigned by Antonio Vazquez

2019-07-05 23:16:35 +02:00

Antonio Vazquez self-assigned this 2019-07-05 23:16:35 +02:00

Antonio Vazquez commented

2019-07-05 23:54:57 +02:00

Changed status from 'Open' to: 'Resolved'

Antonio Vazquez closed this issue

2019-07-05 23:54:57 +02:00

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Grease Pencil selection order is wrong #62101