WebGL Texture Cache Problem

[Benman2785]

Tomb Raider 3dfx: incorrect textures and corrupted menu glyphs after
initialization -> starting game or watching demo; toggling mipmapping with F4 immediately repairs all textures,
and they remain correct after toggling mipmapping off again.

Likely WebGL Voodoo texture cache / texture descriptor invalidation issue.

before

after DEMO with 2x F4 (normal -> mipmap -> normal again)

[Benman2785]

void ogl_cache_texture(const poly_extra_data *extra,
                       ogl_texture_data *td)

std::map<const UINT32, ogl_texmap> textures[2]; + t = textures[j].find(texbase); results in wrong textures if the there was a texture before that in the same texture-cache-address -> the 3DFX Logo (or the EIDOS Video) maps the cache -> the menu of the game then uses a the false texture because both have the same address

you have to check for texture format, width and height, LOD, lodmask (maybe also Clamp-/Repeat-State) and Filter-/MipMap-State)

ALSO:

UINT32 TEXMODE =
    j == 0 ? extra->r_textureMode0 : extra->r_textureMode1;

uses TEXMODE_FORMAT(v->tmu[j].reg[textureMode].u) instead of TEXMODE_FORMAT(TEXMODE) which leads to wrong formatted textures by TMU-State

here some fixes:

const UINT32 TEXMODE =
    j == 0 ? static_cast<UINT32>(extra->r_textureMode0)
           : static_cast<UINT32>(extra->r_textureMode1);

const UINT32 format = TEXMODE_FORMAT(TEXMODE);

results in TEXMODE_FORMAT(v->tmu[j].reg[textureMode].u) being replaced by format

also in void ogl_sh_tex_combine() we need:

const UINT32 TEXMODE =
    TMU == 0 ? static_cast<UINT32>(extra->r_textureMode0)
             : static_cast<UINT32>(extra->r_textureMode1);

native/dosbox-x/src/hardware/voodoo_opengl.h to to be extended:

struct ogl_texmap {
    bool valid_data;
    bool valid_pal;

    UINT32 format;
    UINT32 current_id;

    std::map<const UINT32, GLuint>* ids;

    UINT32 width;
    UINT32 height;
    UINT32 ilod;
    UINT32 lodmask;
    UINT32 texture_mode;
};

and before cache-lookup:

const UINT32 ilod = /* already calculated */;
const UINT32 width  = (v->tmu[j].wmask >> ilod) + 1;
const UINT32 height = (v->tmu[j].hmask >> ilod) + 1;
const UINT32 format = TEXMODE_FORMAT(TEXMODE);

validate cache-hits

auto t = textures[j].find(texbase);

if (t != textures[j].end()) {
    const ogl_texmap& cached = t->second;

    const bool descriptor_changed =
        cached.format       != format ||
        cached.width        != width ||
        cached.height       != height ||
        cached.ilod         != ilod ||
        cached.lodmask      != v->tmu[j].lodmask ||
        cached.texture_mode != TEXMODE;

    if (descriptor_changed) {
        destroy_cached_texture(t->second);
        textures[j].erase(t);
        t = textures[j].end();
    }
}

helper function

static void destroy_cached_texture(ogl_texmap& texture)
{
    if (texture.ids != nullptr) {
        for (const auto& entry : *texture.ids) {
            const GLuint id = entry.second;
            glDeleteTextures(1, &id);
        }

        delete texture.ids;
        texture.ids = nullptr;
    } else if (texture.current_id != 0) {
        glDeleteTextures(1, &texture.current_id);
    }

    texture.current_id = 0;
}

or we simply check the TMU-RAM writes correctly and validate when new pixeldata with the same format is written to the same address...

btw:
extra->texcount && (extra->texcount >= j)
true with texcount == 1 && j == 1 - but should only valid in TMU 0

if (j < extra->texcount &&
    v->tmu[j].lodmin < (8 << 8)) {
    ...
}