Commit c29dc887 authored by Glenn Watson's avatar Glenn Watson Committed by gwatson@mozilla.com
Browse files

Bug 1967840 - Add SWGL extension for applying a R8 alpha mask to a RGBA8... 

Bug 1967840 - Add SWGL extension for applying a R8 alpha mask to a RGBA8 texture r=gfx-reviewers,lsalzman

Differential Revision: https://phabricator.services.mozilla.com/D250524
parent 269bb73b

gfx/wr/swgl/src/composite.h

+53 −0
Original line number Diff line number Diff line
@@ -71,6 +71,40 @@ ALWAYS_INLINE uint8_t convert_pixel<uint8_t>(uint16_t src) { 
#endif

}



// Apply a u8 alpha mask to a u32 texture row

static inline void mask_row(uint32_t* dst, const uint8_t* mask, int span) {

  auto* end = dst + span;

  while (dst + 4 <= end) {

    WideRGBA8 maskpx = expand_mask(dst, unpack(unaligned_load<PackedR8>(mask)));

    WideRGBA8 dstpx = unpack(unaligned_load<PackedRGBA8>(dst));

    PackedRGBA8 r = pack(muldiv255(dstpx, maskpx));

    unaligned_store(dst, r);

    mask += 4;

    dst += 4;

  }

  if (dst < end) {

    WideRGBA8 maskpx = expand_mask(dst, unpack(partial_load_span<PackedR8>(mask, end - dst)));

    WideRGBA8 dstpx = unpack(partial_load_span<PackedRGBA8>(dst, end - dst));

    auto r = pack(maskpx + dstpx - muldiv255(dstpx, maskpx));

    partial_store_span(dst, r, end - dst);

  }

}



// Apply a R8 alpha mask to a RGBA8 texture

static NO_INLINE void mask_blit(Texture& masktex, Texture& dsttex) {

  int maskStride = masktex.stride();

  int destStride = dsttex.stride();

  char* dest = dsttex.sample_ptr(0, 0);

  char* mask = masktex.sample_ptr(0, 0);

  int span = dsttex.width;



  for (int rows = dsttex.height; rows > 0; rows--) {

      mask_row((uint32_t*)dest, (uint8_t*)mask, span);

      dest += destStride;

      mask += maskStride;

  }

}



template <bool COMPOSITE, typename P>

static inline void copy_row(P* dst, const P* src, int span) {

  // No scaling, so just do a fast copy.
@@ -588,6 +622,25 @@ void Composite(LockedTexture* lockedDst, LockedTexture* lockedSrc, GLint srcX, 
  }

}



// Extension used by the SWGL compositor to apply an alpha mask

// to a texture. The textures must be the same size. The mask

// must be R8, the texture must be RGBA8.

void ApplyMask(LockedTexture* lockedDst, LockedTexture* lockedMask) {

  assert(lockedDst);

  assert(lockedMask);



  Texture& masktex = *lockedMask;

  Texture& dsttex = *lockedDst;



  assert(masktex.bpp() == 1);

  assert(dsttex.bpp() == 4);



  assert(masktex.width == dsttex.width);

  assert(masktex.height == dsttex.height);



  mask_blit(masktex, dsttex);

}



}  // extern "C"



// Saturated add helper for YUV conversion. Supported platforms have intrinsics

gfx/wr/swgl/src/swgl_fns.rs

+17 −0
Original line number Diff line number Diff line
@@ -314,6 +314,10 @@ extern "C" { 
        clip_width: GLsizei,

        clip_height: GLsizei,

    );

    fn ApplyMask(

        locked_dst: *mut LockedTexture,

        locked_mask: *mut LockedTexture,

    );

    fn CreateContext() -> *mut c_void;

    fn ReferenceContext(ctx: *mut c_void);

    fn DestroyContext(ctx: *mut c_void);
@@ -2459,6 +2463,19 @@ impl LockedResource { 
        }

    }



    /// Apply an R8 alpha mask to this surface

    pub fn apply_mask(

        &self,

        mask: &LockedResource,

    ) {

        unsafe {

            ApplyMask(

                self.0,

                mask.0,

            );

        }

    }



    /// Get the underlying buffer for a locked resource

    pub fn get_buffer(&self) -> (*mut c_void, i32, i32, i32) {

        unsafe {