Fix text corruption in oversized labels (16-bit text index overflow)

[Schogol]

Summary

Popup windows with a very large amount of text (e.g. contract confirmations with many items, "can't activate" acceleration-gate messages) render corrupt. The text sprite batch used 16-bit indices, which overflow once a single label exceeds 65,535 indices.

Should fix EDR-1989.

Root cause

EVE's font emits 2 quads per glyph = 12 indices/glyph with Text Shadow on, so a single label overflows the 16-bit index space at 65,535 / 12, i.e. about 5,461 visible glyphs. Two 16-bit bottlenecks:

1. Index count: RenderTriangleVerts / EnsureBufferSpace / CopyIndicesWithOffset / GrowCaptureIndexBuffer took unsigned short indexCount, truncating the unsigned int count the font passes (the ~5,461-glyph limit).
2. Index values: Tr2FontMeasurer::m_indices was unsigned short, so per-draw-call vertex indices wrap once a single-texture run exceeds 65,535 vertices (~8,191 glyphs with shadow).

UI text goes through the capture/display-list path, which does not split batches, so the whole label hits these 16-bit boundaries in one submission.

Fix

Widen the text sprite index path to 32-bit:

• Index counts unsigned short -> unsigned int in RenderTriangleVerts (both overloads), EnsureBufferSpace, CopyIndicesWithOffset, GrowCaptureIndexBuffer.
• Index values in Tr2FontMeasurer (m_indices, AdjustIndicesIfNeeded) -> unsigned int, submitted via new 32-bit RenderTriangleVerts / CopyIndicesWithOffset overloads. The existing 16-bit overloads are kept for the other sprite types (frames, lines, brackets) that pass 16-bit index arrays, so their callers are untouched.

The GPU index buffer is already 32-bit (m_indexBuffer.Create(indexCount, 4)), so no GPU format change is needed; this only stops the CPU-side truncation before the data reaches the already-32-bit buffer.

[Ikreb1]

Hi looks promising. Did you test this and does it work?

[Schogol]

It compiles with warnings-as-errors on, and links into both _trinity_dx11 and _trinity_dx12 using python 3.
Unless I'm missing something I dont think I can build it using "BUILD_FOR_PYTHON_2" as I'm missing the Python-2.7 carbon libraries. And without that I cant just pop the files into the EVE game files and test it on a test server.
(If I'm wrong about that then please let me know - I would love to know how I can better test this in a game client in the future)

Previous issue:
The text sprite path had two independent 16-bit chokepoints: the index count (12 indices/glyph with Text Shadow → wraps past 5461 glyphs) and the index values (Tr2FontMeasurer::m_indices → wraps past 8192 glyphs).

I reproduced the overflow and confirmed the fix removes it (standalone demo - not using the compiled dll).
I modeled the exact index arithmetic the engine generates for a label (2 quads/glyph with shadow → 12 indices, max index value 8·glyphs - 1) and ran it with both uint16 and uint32:

Index overflow vs. label size (16-bit vs. 32-bit)

  glyphs | INDEX COUNT (= 12N)        | MAX INDEX VALUE (= 8N-1)
       N |     uint16   uint32(fixed) |     uint16   uint32(fixed)
---------+----------------------------+----------------------------
    5461 |      65532         65532   |      43687          43687
    5462 |     8 WRAP         65544   |      43695          43695     <- index COUNT overflows (5462 glyphs)
    8192 | 32768 WRAP         98304   |      65535          65535
    8193 | 32780 WRAP         98316   |     7 WRAP          65543     <- index VALUES overflow (8193 glyphs)
   10000 | 54464 WRAP        120000   | 14463 WRAP          79999