hud translucent

[Hazematman]

does standard glquake have support for translucent textures for the hud?

if so, how would I make it draw a translucent picture?

if not, does anyone know how to add it and could try to help me with it?

[Baker]

Yes it does.

Something like Draw_AlphaPic and if it doesn't, you can easily make one by turning on whatever r_wateralpha does on, presumably, the PSP.

In OpenGL, it something like GLBlendEnable and glColor4f (might be slightly off, not looking @ the engine code). I can't remember the PSPGU equivalent.

[Sajt]

Draw_TransPic draws images with TRANSPARENT pixels (palette index 255). But "translucent" means fadey-alpha. I don't think GLQuake supports that out of the box.

[r00k]

Code: Select all

void Sbar_DrawPicAlpha (int x, int y, mpic_t *pic)
{   
   Draw_AlphaPic (x + sbar_xofs, y + (vid.height-SBAR_HEIGHT), pic, scr_sbaralpha.value);
}


Code: Select all

/*
=============
Draw_AlphaPic
=============
*/
void Draw_AlphaPic (int x, int y, mpic_t *pic, float alpha)
{
   if (scrap_dirty)
      Scrap_Upload ();

   glDisable(GL_ALPHA_TEST);
   glEnable (GL_BLEND);
   glCullFace (GL_FRONT);
   glColor4f (1, 1, 1, alpha);
   GL_Bind (pic->texnum);
   
   glBegin (GL_QUADS);
   glTexCoord2f (pic->sl, pic->tl);
   glVertex2f (x, y);
   glTexCoord2f (pic->sh, pic->tl);
   glVertex2f (x+pic->width, y);
   glTexCoord2f (pic->sh, pic->th);
   glVertex2f (x+pic->width, y+pic->height);
   glTexCoord2f (pic->sl, pic->th);
   glVertex2f (x, y+pic->height);
   glEnd ();

   glColor3f (1, 1, 1);
   glEnable(GL_ALPHA_TEST);
   glDisable (GL_BLEND);
}


[Sajt]

I stand corrected. I've never spent much time in the GLQuake source but I should have looked before I posted.

Anyway, it's still not clear what the original poster wanted. Constant alpha over the whole image (Draw_AlphaPic) or an image with an alpha channel... Probably the former. I'll go now...

[Baker]

I wasn't 100% sure it was in GLQuake for sure either, then again I think I recall one version having a translucent console or something?

Since it is in GLQuake, PSP engines have equivalent, of course:

Code: Select all

/*
=============
Draw_AlphaPic
=============
*/
static void Draw_AlphaPic (int x, int y, qpic_t *pic, float alpha)
{
   if (alpha != 1.0f)
   {
      sceGuTexFunc(GU_TFX_DECAL, GU_TCC_RGBA);
   }

   glpic_t         *gl;

#if 0
   if (scrap_dirty)
      Scrap_Upload ();
#endif
   gl = (glpic_t *)pic->data;
   GL_Bind (gl->index);

   const gltexture_t& glt = gltextures[gl->index];

   struct vertex
   {
      short         u, v;
      short         x, y, z;
   };

   int start, end;
   int slice = 32;

   // blit maximizing the use of the texture-cache

   for (start = 0, end = glt.original_width; start < end; start += slice, x += slice)
   {
        vertex* const vertices = static_cast<vertex*>(sceGuGetMemory(sizeof(vertex) * 2));
        int width = (start + slice) < end ? slice : end-start;

        vertices[0].u      = start;
        vertices[0].v      = 0;
        vertices[0].x      = x;
        vertices[0].y      = y;
        vertices[0].z      = 0;

        vertices[1].u      = start + width;//glt.original_width;
        vertices[1].v      = glt.original_height;
        vertices[1].x      = x + width;//pic->width;
        vertices[1].y      = y + pic->height;
        vertices[1].z      = 0;

        sceGuColor(GU_RGBA(0xff, 0xff, 0xff, static_cast<unsigned int>(alpha * 255.0f)));
        sceGuDrawArray(GU_SPRITES,GU_TEXTURE_16BIT | GU_VERTEX_16BIT | GU_TRANSFORM_2D, 2, 0, vertices);
   }
   if (alpha != 1.0f)
      sceGuTexFunc(GU_TFX_REPLACE, GU_TCC_RGBA);
}

[r00k]

draw_alpha pic available but i dont think glQuake used it for the sbar.

[Sajt]

Probably only for the conback.

[leileilol]

Probably only for the conback.

indeed since the conback fades.

FUN FACT: the rage pro is stupid with alphas and TRIES TO SOFTWARE RENDER THEM WITHIN THE 3D BUFFER, maybe that's why it's hardly used.

[Mexicouger]

Where the heck is Sbar_DrawPicAlpha located? Which file? I did a complete search in psp Kurok, and I fail to find it using textpad5/.

[revelator]

normally in gl_draw.c allthough i dunno about the psp source.

[mh]

You've got the name wrong - it's Draw_AlphaPic.

Another fun fact: GLQuake's Draw_AlphaPic is actually broken and won't draw with alpha at all on most (all?) modern 3D cards.

[Baker]

You will have to copy Sbar_DrawPic and make your own Sbar_DrawAlphaPic.

It is a trivial change, just add one more field called alpha to the end of the function declaration (i.e. float alpha).

Then in Sbar_DrawAlphaPic make it use Draw_AlphaPic if the alpha value is less than 1.

if (alpha < 1)
Draw_AlphaPic (...., alpha);
else
Draw_Pic (....);

Post back if you need help, unfortunately these next several days I may only be around 15 minutes twice per day but any other engine coder can help you with this because it is a very basic modification.

[revelator]

yup i actually think its somewhere in the old qsg tutorial archives it was mentioned first time translucent hud something...

[revelator]

found it.

/*=============
Draw_Pic
=============*/
void Draw_Pic (int x, int y, qpic_t *pic, float alpha)
{
byte *dest, *source;
unsigned short *pusdest;
int v, u;
glpic_t *gl;

if (scrap_dirty)
Scrap_Upload ();

gl = (glpic_t *)pic->data;

glEnable (GL_BLEND);
glColor4f (1,1,1,alpha);

GL_Bind (gl->texnum);
glBegin (GL_QUADS);
glTexCoord2f (gl->sl, gl->tl);
glVertex2f (x, y);
glTexCoord2f (gl->sh, gl->tl);
glVertex2f (x+pic->width, y);
glTexCoord2f (gl->sh, gl->th);
glVertex2f (x+pic->width, y+pic->height);
glTexCoord2f (gl->sl, gl->th);
glVertex2f (x, y+pic->height);
glEnd ();

glColor4f (1,1,1,1);
glDisable (GL_BLEND);
}[/code]