BLF: Perf: Divide by 6 the amount of verts sent to the GPU.

This means smaller imm buffer usage.

This does not reduce the number of drawcalls.

This uses geometry shader which is slow for the GPU but given we are really
CPU bound on this case, it should not matter.

A perfect implementation would:
- Set the glyph coord in a bufferTexture and just send the glyph ID to the
  GPU to read the bufferTexture.
- Use GWN_draw_primitive and draw 2*strllen triangle and just retrieve the
  glyph ID and color based on gl_VertexID / 6.
- Stream fixed size buffer that the Driver can discard quickly but this is
  the same as improving IMM directly.

1 files changed, 3 insertions, 3 deletions

diff --git a/source/blender/blenfont/intern/blf.c b/source/blender/blenfont/intern/blf.c
index 8e705616c41..30919f1acda 100644
--- a/source/blender/blenfont/intern/blf.c
+++ b/source/blender/blenfont/intern/blf.c
@@ -579,9 +579,9 @@ static void blf_draw_gl__start(FontBLF *font)
 
 #ifndef BLF_STANDALONE
 	Gwn_VertFormat *format = immVertexFormat();
-	unsigned int pos = GWN_vertformat_attr_add(format, "pos", GWN_COMP_F32, 2, GWN_FETCH_FLOAT);
-	unsigned int texCoord = GWN_vertformat_attr_add(format, "texCoord", GWN_COMP_F32, 2, GWN_FETCH_FLOAT);
-	unsigned int color = GWN_vertformat_attr_add(format, "color", GWN_COMP_U8, 4, GWN_FETCH_INT_TO_FLOAT_UNIT);
+	unsigned int pos = GWN_vertformat_attr_add(format, "pos", GWN_COMP_F32, 4, GWN_FETCH_FLOAT);
+	unsigned int texCoord = GWN_vertformat_attr_add(format, "tex", GWN_COMP_F32, 4, GWN_FETCH_FLOAT);
+	unsigned int color = GWN_vertformat_attr_add(format, "col", GWN_COMP_U8, 4, GWN_FETCH_INT_TO_FLOAT_UNIT);
 
 	BLI_assert(pos == BLF_POS_ID);
 	BLI_assert(texCoord == BLF_COORD_ID);