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Rewrite Voodoo triangle setup vertex selection code. Fixes missing triangles

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on Banshee with some D3D games (eg Black & White, Viper Racing)
This commit is contained in:
SarahW 2020-08-31 13:31:23 +01:00
commit fb391d2484
2 changed files with 56 additions and 9 deletions
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3
src/vid_voodoo_common.h
View file

@ -306,7 +306,8 @@ typedef struct voodoo_t
uint32_t sSetupMode;
vert_t verts[4];
int vertex_num;
unsigned int vertex_ages[3];
unsigned int vertex_next_age;
int num_verticies;
int cull_pingpong;

62
src/vid_voodoo_reg.c
View file

@ -683,18 +683,66 @@ void voodoo_reg_writel(uint32_t addr, uint32_t val, void *p)
case SST_sBeginTriCMD:
// pclog("sBeginTriCMD %i %f\n", voodoo->vertex_num, voodoo->verts[4].sVx);
voodoo->verts[0] = voodoo->verts[3];
voodoo->vertex_num = 1;
voodoo->verts[1] = voodoo->verts[3];
voodoo->verts[2] = voodoo->verts[3];
voodoo->vertex_next_age = 0;
voodoo->vertex_ages[0] = voodoo->vertex_next_age++;
voodoo->num_verticies = 1;
voodoo->cull_pingpong = 0;
break;
case SST_sDrawTriCMD:
// pclog("sDrawTriCMD %i %i %i\n", voodoo->num_verticies, voodoo->vertex_num, voodoo->sSetupMode & SETUPMODE_STRIP_MODE);
if (voodoo->vertex_num == 3)
voodoo->vertex_num = (voodoo->sSetupMode & SETUPMODE_STRIP_MODE) ? 1 : 0;
voodoo->verts[voodoo->vertex_num] = voodoo->verts[3];
// pclog("sDrawTriCMD %i %i\n", voodoo->num_verticies, voodoo->sSetupMode & SETUPMODE_STRIP_MODE);
/*I'm not sure this is the vertex selection algorithm actually used in the 3dfx
chips, but this works with a number of games that switch between strip and fan
mode in the middle of a run (eg Black & White, Viper Racing)*/
if (voodoo->vertex_next_age < 3)
{
/*Fewer than three vertices already written, store in next slot*/
int vertex_nr = voodoo->vertex_next_age;
voodoo->verts[vertex_nr] = voodoo->verts[3];
voodoo->vertex_ages[vertex_nr] = voodoo->vertex_next_age++;
}
else
{
int vertex_nr = 0;
if (!(voodoo->sSetupMode & SETUPMODE_STRIP_MODE))
{
/*Strip - find oldest vertex*/
if ((voodoo->vertex_ages[0] < voodoo->vertex_ages[1]) &&
(voodoo->vertex_ages[0] < voodoo->vertex_ages[2]))
vertex_nr = 0;
else if ((voodoo->vertex_ages[1] < voodoo->vertex_ages[0]) &&
(voodoo->vertex_ages[1] < voodoo->vertex_ages[2]))
vertex_nr = 1;
else
vertex_nr = 2;
}
else
{
/*Fan - find second oldest vertex (ie pivot around oldest)*/
if ((voodoo->vertex_ages[1] < voodoo->vertex_ages[0]) &&
(voodoo->vertex_ages[0] < voodoo->vertex_ages[2]))
vertex_nr = 0;
else if ((voodoo->vertex_ages[2] < voodoo->vertex_ages[0]) &&
(voodoo->vertex_ages[0] < voodoo->vertex_ages[1]))
vertex_nr = 0;
else if ((voodoo->vertex_ages[0] < voodoo->vertex_ages[1]) &&
(voodoo->vertex_ages[1] < voodoo->vertex_ages[2]))
vertex_nr = 1;
else if ((voodoo->vertex_ages[2] < voodoo->vertex_ages[1]) &&
(voodoo->vertex_ages[1] < voodoo->vertex_ages[0]))
vertex_nr = 1;
else
vertex_nr = 2;
}
voodoo->verts[vertex_nr] = voodoo->verts[3];
voodoo->vertex_ages[vertex_nr] = voodoo->vertex_next_age++;
}
voodoo->num_verticies++;
voodoo->vertex_num++;
if (voodoo->num_verticies == 3)
{
// pclog("triangle_setup\n");
@ -703,8 +751,6 @@ void voodoo_reg_writel(uint32_t addr, uint32_t val, void *p)
voodoo->num_verticies = 2;
}
if (voodoo->vertex_num == 4)
fatal("sDrawTriCMD overflow\n");
break;
case SST_bltSrcBaseAddr: