Make texel conversion ignore unused channels

The convertNormalizedUnsignedFixedPoint function applied conversion to
all channels, even those with 0 bit width, causing a bunch of division
by zeros. The change skips all non-used channels.

Affects:
KHR-GLES3.copy_tex_image_conversions.*

Components: OpenGL
VK-GL-CTS issue: 3354

Change-Id: I88bf9748bd7226c8c41ea44a1df9fabf0f648cfa

diff --git a/external/openglcts/modules/gles3/es3cCopyTexImageConversionsTests.cpp b/external/openglcts/modules/gles3/es3cCopyTexImageConversionsTests.cpp
index aea6a01..4faa571 100644 (file)
--- a/external/openglcts/modules/gles3/es3cCopyTexImageConversionsTests.cpp
+++ b/external/openglcts/modules/gles3/es3cCopyTexImageConversionsTests.cpp
@@ -606,18 +606,21 @@ bool ConversionDatabase::convertNormalizedUnsignedFixedPoint(int* src_input_rgba
 
        for (unsigned int n = 0; n < sizeof(bit_diffs_src_intermediate) / sizeof(bit_diffs_src_intermediate[0]); ++n)
        {
-               float tmp = ((float)src_rgba_intermediate[n]) / ((1 << src_input_rgba_bits[n]) - 1);
-               if (tmp > 1.0f)
-                       tmp = 1.0f;
-               tmp *= (float)((1 << src_attachment_rgba_bits[n]) - 1);
-               src_rgba_intermediate[n] = (int)(0.5 + tmp);
+               if (src_input_rgba_bits[n] != 0)
+               {
+                       float tmp = ((float)src_rgba_intermediate[n]) / ((1 << src_input_rgba_bits[n]) - 1);
+                       if (tmp > 1.0f)
+                               tmp = 1.0f;
+                       tmp *= (float)((1 << src_attachment_rgba_bits[n]) - 1);
+                       src_rgba_intermediate[n] = (int)(0.5 + tmp);
+               }
        }
 
        // The following equations correspond to equation 2.1 from ES spec 3.0.2
-       r_f32 = ((float)src_rgba_intermediate[0]) / (float)((1 << src_attachment_rgba_bits[0]) - 1);
-       g_f32 = ((float)src_rgba_intermediate[1]) / (float)((1 << src_attachment_rgba_bits[1]) - 1);
-       b_f32 = ((float)src_rgba_intermediate[2]) / (float)((1 << src_attachment_rgba_bits[2]) - 1);
-       a_f32 = ((float)src_rgba_intermediate[3]) / (float)((1 << src_attachment_rgba_bits[3]) - 1);
+       if (src_attachment_rgba_bits[0] != 0) r_f32 = ((float)src_rgba_intermediate[0]) / (float)((1 << src_attachment_rgba_bits[0]) - 1);
+       if (src_attachment_rgba_bits[1] != 0) g_f32 = ((float)src_rgba_intermediate[1]) / (float)((1 << src_attachment_rgba_bits[1]) - 1);
+       if (src_attachment_rgba_bits[2] != 0) b_f32 = ((float)src_rgba_intermediate[2]) / (float)((1 << src_attachment_rgba_bits[2]) - 1);
+       if (src_attachment_rgba_bits[3] != 0) a_f32 = ((float)src_rgba_intermediate[3]) / (float)((1 << src_attachment_rgba_bits[3]) - 1);
 
        // Clamp to <0, 1>. Since we're dealing with unsigned ints on input, there's
        // no way we could be lower than 0.
@@ -665,11 +668,14 @@ bool ConversionDatabase::convertNormalizedUnsignedFixedPoint(int* src_input_rgba
 
        for (unsigned int n = 0; n < 4 /* channels */; ++n)
        {
-               float tmp = ((float)dst_rgba[n]) / ((1 << dst_attachment_rgba_bits[n]) - 1);
-               if (tmp > 1.0f)
-                       tmp = 1.0f;
-               tmp *= (float)((1 << dst_output_rgba_bits[n]) - 1);
-               dst_rgba[n] = (int)(0.5 + tmp);
+               if (dst_attachment_rgba_bits[n] != 0)
+               {
+                       float tmp = ((float)dst_rgba[n]) / ((1 << dst_attachment_rgba_bits[n]) - 1);
+                       if (tmp > 1.0f)
+                               tmp = 1.0f;
+                       tmp *= (float)((1 << dst_output_rgba_bits[n]) - 1);
+                       dst_rgba[n] = (int)(0.5 + tmp);
+               }
        }
 
        return true;