UI: Perf: widgetbase: Replace imm usage by a batch cache.

Introduce a UI batch cache. For the moment it's only used by widgetbase so
leaving it interface_widgets.c. If it grows, it can have its own file.

Like all preset batches (batches used by UI context), vaos must be refreshed
each time a new window context is binded.

This still does 3 GWN_batch_draw in the worst cases but at least it does
not use the IMM api.

I will continue and batch the 3 calls together since we are really CPU
bound, so shader complexity does not really matters.

I cannot spot any difference on all the widgets I could test. I did not use
any unit tests so I cannot tell if there is really any defects.

This is not a complete rewrite but it adresses the top bottleneck found
after a profilling session.

1 files changed, 6 insertions, 0 deletions

diff --git a/source/blender/gpu/intern/gpu_batch_presets.c b/source/blender/gpu/intern/gpu_batch_presets.c
index 696143a3857..1eb1b737bee 100644
--- a/source/blender/gpu/intern/gpu_batch_presets.c
+++ b/source/blender/gpu/intern/gpu_batch_presets.c
@@ -33,6 +33,8 @@
 #include "BLI_math.h"
 #include "BLI_threads.h"
 
+#include "UI_interface.h"
+
 #include "GPU_batch.h"
 #include "gpu_shader_private.h"
 
@@ -202,6 +204,8 @@ void gpu_batch_presets_reset(void)
 	gwn_batch_vao_cache_clear(g_presets_3d.batch.sphere_high);
 	gwn_batch_vao_cache_clear(g_presets_3d.batch.sphere_wire_low);
 	gwn_batch_vao_cache_clear(g_presets_3d.batch.sphere_wire_med);
+
+	ui_widget_batch_preset_reset();
 }
 
 void gpu_batch_presets_exit(void)
@@ -211,4 +215,6 @@ void gpu_batch_presets_exit(void)
 	GWN_batch_discard(g_presets_3d.batch.sphere_high);
 	GWN_batch_discard(g_presets_3d.batch.sphere_wire_low);
 	GWN_batch_discard(g_presets_3d.batch.sphere_wire_med);
+
+	ui_widget_batch_preset_exit();
 }