vbe.c

grub 1.95 linux 的bootloader 源代码

          return;
        }

      *red = framebuffer.palette[color].r;
      *green = framebuffer.palette[color].g;
      *blue = framebuffer.palette[color].b;
      *alpha = framebuffer.palette[color].a;
      return;
    }
  else
    {
      grub_uint32_t tmp;

      /* Get red component.  */
      tmp = color >> mode_info->red_field_pos;
      tmp &= (1 << mode_info->red_mask_size) - 1;
      tmp <<= 8 - mode_info->red_mask_size;
      tmp |= (1 << (8 - mode_info->red_mask_size)) - 1;
      *red = tmp & 0xFF;

      /* Get green component.  */
      tmp = color >> mode_info->green_field_pos;
      tmp &= (1 << mode_info->green_mask_size) - 1;
      tmp <<= 8 - mode_info->green_mask_size;
      tmp |= (1 << (8 - mode_info->green_mask_size)) - 1;
      *green = tmp & 0xFF;

      /* Get blue component.  */
      tmp = color >> mode_info->blue_field_pos;
      tmp &= (1 << mode_info->blue_mask_size) - 1;
      tmp <<= 8 - mode_info->blue_mask_size;
      tmp |= (1 << (8 - mode_info->blue_mask_size)) - 1;
      *blue = tmp & 0xFF;

      /* Get alpha component.  */
      if (source->mode_info->reserved_mask_size > 0)
        {
          tmp = color >> mode_info->reserved_field_pos;
          tmp &= (1 << mode_info->reserved_mask_size) - 1;
          tmp <<= 8 - mode_info->reserved_mask_size;
          tmp |= (1 << (8 - mode_info->reserved_mask_size)) - 1;
        }
      else
        /* If there is no alpha component, assume it opaque.  */
        tmp = 255;

      *alpha = tmp & 0xFF;
    }
}

static grub_err_t
grub_video_vbe_fill_rect (grub_video_color_t color, int x, int y,
                          unsigned int width, unsigned int height)
{
  struct grub_video_i386_vbeblit_info target;

  /* Make sure there is something to do.  */
  if ((x >= (int)render_target->viewport.width) || (x + (int)width < 0))
    return GRUB_ERR_NONE;
  if ((y >= (int)render_target->viewport.height) || (y + (int)height < 0))
    return GRUB_ERR_NONE;

  /* Do not allow drawing out of viewport.  */
  if (x < 0)
    {
      width += x;
      x = 0;
    }
  if (y < 0)
    {
      height += y;
      y = 0;
    }

  if ((x + width) > render_target->viewport.width)
    width = render_target->viewport.width - x;
  if ((y + height) > render_target->viewport.height)
    height = render_target->viewport.height - y;

  /* Add viewport offset.  */
  x += render_target->viewport.x;
  y += render_target->viewport.y;

  /* Use vbeblit_info to encapsulate rendering.  */
  target.mode_info = &render_target->mode_info;
  target.data = render_target->data;

  /* Try to figure out more optimized version.  */
  if (target.mode_info->blit_format == GRUB_VIDEO_BLIT_FORMAT_R8G8B8A8)
    {
      grub_video_i386_vbefill_R8G8B8A8 (&target, color, x, y, 
                                        width, height);
      return GRUB_ERR_NONE;
    }

  if (target.mode_info->blit_format == GRUB_VIDEO_BLIT_FORMAT_R8G8B8)
    {
      grub_video_i386_vbefill_R8G8B8 (&target, color, x, y,
                                      width, height);
      return GRUB_ERR_NONE;
    }

  if (target.mode_info->blit_format == GRUB_VIDEO_BLIT_FORMAT_INDEXCOLOR)
    {
      grub_video_i386_vbefill_index (&target, color, x, y,
                                     width, height);
      return GRUB_ERR_NONE;
    }

  /* No optimized version found, use default (slow) filler.  */
  grub_video_i386_vbefill (&target, color, x, y, width, height);

  return GRUB_ERR_NONE;
}

// TODO: Remove this method and replace with bitmap based glyphs
static grub_err_t
grub_video_vbe_blit_glyph (struct grub_font_glyph * glyph,
                           grub_video_color_t color, int x, int y)
{
  struct grub_video_i386_vbeblit_info target;
  unsigned int width;
  unsigned int charwidth;
  unsigned int height;
  unsigned int i;
  unsigned int j;
  unsigned int x_offset = 0;
  unsigned int y_offset = 0;

  /* Make sure there is something to do.  */
  if (x >= (int)render_target->viewport.width)
    return GRUB_ERR_NONE;

  if (y >= (int)render_target->viewport.height)
    return GRUB_ERR_NONE;

  /* Calculate glyph dimensions.  */
  width = ((glyph->width + 7) / 8) * 8;
  charwidth = width;
  height = glyph->height;

  if (x + (int)width < 0)
    return GRUB_ERR_NONE;

  if (y + (int)height < 0)
    return GRUB_ERR_NONE;

  /* Do not allow drawing out of viewport.  */
  if (x < 0)
    {
      width += x;
      x_offset = (unsigned int)-x;
      x = 0;
    }
  if (y < 0)
    {
      height += y;
      y_offset = (unsigned int)-y;
      y = 0;
    }

  if ((x + width) > render_target->viewport.width)
    width = render_target->viewport.width - x;
  if ((y + height) > render_target->viewport.height)
    height = render_target->viewport.height - y;

  /* Add viewport offset.  */
  x += render_target->viewport.x;
  y += render_target->viewport.y;

  /* Use vbeblit_info to encapsulate rendering.  */
  target.mode_info = &render_target->mode_info;
  target.data = render_target->data;

  /* Draw glyph.  */
  for (j = 0; j < height; j++)
    for (i = 0; i < width; i++)
      if ((glyph->bitmap[((i + x_offset) / 8) 
                         + (j + y_offset) * (charwidth / 8)] 
           & (1 << ((charwidth - (i + x_offset) - 1) % 8))))
        set_pixel (&target, x+i, y+j, color);

  return GRUB_ERR_NONE;
}

/* NOTE: This function assumes that given coordiantes are within bounds of 
   handled data.  */
static void
common_blitter (struct grub_video_i386_vbeblit_info *target,
                struct grub_video_i386_vbeblit_info *source,
                enum grub_video_blit_operators oper, int x, int y,
                unsigned int width, unsigned int height,
                int offset_x, int offset_y)
{
  if (oper == GRUB_VIDEO_BLIT_REPLACE)
    {
      /* Try to figure out more optimized version for replace operator.  */
      if (source->mode_info->blit_format == GRUB_VIDEO_BLIT_FORMAT_R8G8B8A8)
        {
          if (target->mode_info->blit_format == GRUB_VIDEO_BLIT_FORMAT_R8G8B8A8)
            {
              grub_video_i386_vbeblit_R8G8B8X8_R8G8B8X8 (target, source,
                                                         x, y, width, height,
                                                         offset_x, offset_y);
              return;
            }

          if (target->mode_info->blit_format == GRUB_VIDEO_BLIT_FORMAT_R8G8B8)
            {
              grub_video_i386_vbeblit_R8G8B8_R8G8B8X8 (target, source,
                                                       x, y, width, height,
                                                       offset_x, offset_y);
              return;
            }

          if (target->mode_info->blit_format == GRUB_VIDEO_BLIT_FORMAT_INDEXCOLOR)
            {
              grub_video_i386_vbeblit_index_R8G8B8X8 (target, source,
                                                      x, y, width, height,
                                                      offset_x, offset_y);
              return;
            }
        }

      if (source->mode_info->blit_format == GRUB_VIDEO_BLIT_FORMAT_R8G8B8)
        {
          if (target->mode_info->blit_format == GRUB_VIDEO_BLIT_FORMAT_R8G8B8A8)
            {
              grub_video_i386_vbeblit_R8G8B8A8_R8G8B8 (target, source,
                                                       x, y, width, height,
                                                       offset_x, offset_y);
              return;
            }

          if (target->mode_info->blit_format == GRUB_VIDEO_BLIT_FORMAT_R8G8B8)
            {
              grub_video_i386_vbeblit_R8G8B8_R8G8B8 (target, source,
                                                     x, y, width, height,
                                                     offset_x, offset_y);
              return;
            }

          if (target->mode_info->blit_format == GRUB_VIDEO_BLIT_FORMAT_INDEXCOLOR)
            {
              grub_video_i386_vbeblit_index_R8G8B8 (target, source,
                                                    x, y, width, height,
                                                    offset_x, offset_y);
              return;
            }
        }

      if (source->mode_info->blit_format == GRUB_VIDEO_BLIT_FORMAT_INDEXCOLOR)
        {
          if (target->mode_info->blit_format == GRUB_VIDEO_BLIT_FORMAT_INDEXCOLOR)
            {
              grub_video_i386_vbeblit_index_index (target, source,
                                                   x, y, width, height,
                                                   offset_x, offset_y);
              return;
            }
        }

      /* No optimized replace operator found, use default (slow) blitter.  */
      grub_video_i386_vbeblit_replace (target, source, x, y, width, height,
                                       offset_x, offset_y);
    }
  else
    {
      /* Try to figure out more optimized blend operator.  */
      if (source->mode_info->blit_format == GRUB_VIDEO_BLIT_FORMAT_R8G8B8A8)
      {
        if (target->mode_info->blit_format == GRUB_VIDEO_BLIT_FORMAT_R8G8B8A8)
        {
          grub_video_i386_vbeblit_R8G8B8A8_R8G8B8A8 (target, source,
              x, y, width, height,
              offset_x, offset_y);
          return;
        }

        if (target->mode_info->blit_format == GRUB_VIDEO_BLIT_FORMAT_R8G8B8)
        {
          grub_video_i386_vbeblit_R8G8B8_R8G8B8A8 (target, source,
              x, y, width, height,
              offset_x, offset_y);
          return;
        }

        if (target->mode_info->blit_format == GRUB_VIDEO_BLIT_FORMAT_INDEXCOLOR)
        {
          grub_video_i386_vbeblit_index_R8G8B8A8 (target, source,
              x, y, width, height,
              offset_x, offset_y);
          return;
        }
      }

      if (source->mode_info->blit_format == GRUB_VIDEO_BLIT_FORMAT_R8G8B8)
      {
        if (target->mode_info->blit_format == GRUB_VIDEO_BLIT_FORMAT_R8G8B8A8)
        {
          grub_video_i386_vbeblit_R8G8B8A8_R8G8B8 (target, source,
              x, y, width, height,
              offset_x, offset_y);
          return;
        }

        if (target->mode_info->blit_format == GRUB_VIDEO_BLIT_FORMAT_R8G8B8)
        {
          grub_video_i386_vbeblit_R8G8B8_R8G8B8 (target, source,
              x, y, width, height,
              offset_x, offset_y);
          return;
        }

        if (target->mode_info->blit_format == GRUB_VIDEO_BLIT_FORMAT_INDEXCOLOR)
        {
          grub_video_i386_vbeblit_index_R8G8B8 (target, source,
              x, y, width, height,
              offset_x, offset_y);
          return;
        }
      }

      if (source->mode_info->blit_format == GRUB_VIDEO_BLIT_FORMAT_INDEXCOLOR)
      {
        if (target->mode_info->blit_format == GRUB_VIDEO_BLIT_FORMAT_INDEXCOLOR)
        {
          grub_video_i386_vbeblit_index_index (target, source,
                                               x, y, width, height,
                                               offset_x, offset_y);
          return;
        }
      }

      /* No optimized blend operation found, use default (slow) blitter.  */
      grub_video_i386_vbeblit_blend (target, source, x, y, width, height,
                                     offset_x, offset_y);
    }
}

static grub_err_t
grub_video_vbe_blit_bitmap (struct grub_video_bitmap *bitmap,
                            enum grub_video_blit_operators oper, int x, int y,
                            int offset_x, int offset_y,
                            unsigned int width, unsigned int height)
{
  struct grub_video_i386_vbeblit_info source;
  struct grub_video_i386_vbeblit_info target;

  /* Make sure there is something to do.  */
  if ((width == 0) || (height == 0))
    return GRUB_ERR_NONE;
  if ((x >= (int)render_target->viewport.width) || (x + (int)width < 0))
    return GRUB_ERR_NONE;
  if ((y >= (int)render_target->viewport.height) || (y + (int)height < 0))
    return GRUB_ERR_NONE;
  if ((x + (int)bitmap->mode_info.width) < 0)
    return GRUB_ERR_NONE;
  if ((y + (int)bitmap->mode_info.height) < 0)
    return GRUB_ERR_NONE;
  if ((offset_x >= (int)bitmap->mode_info.width) 
      || (offset_x + (int)width < 0))
    return GRUB_ERR_NONE;
  if ((offset_y >= (int)bitmap->mode_info.height) 
      || (offset_y + (int)height < 0))
    return GRUB_ERR_NONE;

  /* If we have negative coordinates, optimize drawing to minimum.  */
  if (offset_x < 0)
    {
      width += offset_x;
      x -= offset_x;
      offset_x = 0;
    }

  if (offset_y < 0)
    {
      height += offset_y;
      y -= offset_y;
      offset_y = 0;
    }

  if (x < 0)
    {
      width += x;
      offset_x -= x;
      x = 0;
    }