diff options
| -rw-r--r-- | indra/llrender/llimagegl.cpp | 43 |
1 files changed, 34 insertions, 9 deletions
diff --git a/indra/llrender/llimagegl.cpp b/indra/llrender/llimagegl.cpp index 00f0fd5b9a..2f02ccf30b 100644 --- a/indra/llrender/llimagegl.cpp +++ b/indra/llrender/llimagegl.cpp @@ -1653,6 +1653,7 @@ void LLImageGL::analyzeAlpha(const void* data_in, U32 w, U32 h) } U32 length = w * h; + U32 alphatotal = 0; U32 sample[16]; memset(sample, 0, sizeof(U32)*16); @@ -1672,11 +1673,15 @@ void LLImageGL::analyzeAlpha(const void* data_in, U32 w, U32 h) const GLubyte* current = rowstart; for (U32 x = 0; x < w; x+=2) { - U32 s1 = current[0]; - U32 s2 = current[w * mAlphaStride]; + const U32 s1 = current[0]; + alphatotal += s1; + const U32 s2 = current[w * mAlphaStride]; + alphatotal += s2; current += mAlphaStride; - U32 s3 = current[0]; - U32 s4 = current[w * mAlphaStride]; + const U32 s3 = current[0]; + alphatotal += s3; + const U32 s4 = current[w * mAlphaStride]; + alphatotal += s4; current += mAlphaStride; ++sample[s1/16]; @@ -1684,19 +1689,23 @@ void LLImageGL::analyzeAlpha(const void* data_in, U32 w, U32 h) ++sample[s3/16]; ++sample[s4/16]; - sample[(s1+s2+s3+s4)/(16 * 4)] += 4; + const U32 asum = (s1+s2+s3+s4); + alphatotal += asum; + sample[asum/(16*4)] += 4; } rowstart += 2 * w * mAlphaStride; } - length += length; + length *= 2; // we sampled everything twice, essentially } else { const GLubyte* current = ((const GLubyte*) data_in) + mAlphaOffset; for (U32 i = 0; i < length; i++) { - ++sample[*current/16]; + const U32 s1 = *current; + alphatotal += s1; + ++sample[s1/16]; current += mAlphaStride; } } @@ -1704,15 +1713,31 @@ void LLImageGL::analyzeAlpha(const void* data_in, U32 w, U32 h) // if more than 1/16th of alpha samples are mid-range, this // shouldn't be treated as a 1-bit mask + // also, if all of the alpha samples are clumped on one half + // of the range (but not at an absolute extreme), then consider + // this to be an intentional effect and don't treat as a mask. + U32 midrangetotal = 0; for (U32 i = 4; i < 11; i++) { midrangetotal += sample[i]; } + U32 lowerhalftotal = 0; + for (U32 i = 0; i < 8; i++) + { + lowerhalftotal += sample[i]; + } + U32 upperhalftotal = 0; + for (U32 i = 8; i < 16; i++) + { + upperhalftotal += sample[i]; + } - if (midrangetotal > length/16) + if (midrangetotal > length/16 || // lots of midrange, or + (lowerhalftotal == length && alphatotal != 0) || // all close to transparent but not all totally transparent, or + (upperhalftotal == length && alphatotal != 255*length)) // all close to opaque but not all totally opaque { - mIsMask = FALSE; + mIsMask = FALSE; // not suitable for masking } else { |