Shader doesn't compile on Fire Stick 4K

A Fully updated Fire Stick 4K here.

GL_VERSION : GL Version OpenGL ES 3.2 build 1.9@4893595
GL_RENDERER: GL Renderer PowerVR Rogue GE8300

I’ve got a shader that fails to compile. glGetShaderInfoLog() returns a cryptic “Compile failed”. That’s it!
This shader compiles (and works) just fine on many Adreno, Mali & Tegra GPUs. It also compiles (and works) just fine on PowerVR GX6250. Problem only on PowerVR GE8100 and GE 8300.

Vertex shader:

#version 310 es
precision highp float;
precision highp int;

in vec2 a_Position;         
out vec2 v_TexCoordinate;
out vec2 v_Pixel;
uniform uvec2 u_Size;       

void main()
  {
  v_TexCoordinate = (a_Position + 0.5);
  v_Pixel         = (a_Position + 0.5) * vec2(u_Size);
  gl_Position     = vec4(2.0*a_Position,1.0,1.0);
  }

Fragment shader:

#version 310 es
precision highp float;
precision highp int;

out vec4 fragColor;           // The output color
in vec2 v_TexCoordinate;      // Interpolated texture coordinate per fragment.
in vec2 v_Pixel;              // location of the current fragment, in pixels

//////////////////////////////////////////////////////////////////////////////////////////////
// per-pixel linked list. Order Independent Transparency.

uniform uvec2 u_Size;

layout (std430,binding=1) buffer linkedlist  // first (u_Size.x*u_Size.y) uints - head pointers,
  {                                          // one for each pixel in the Output rectangle.
  uint u_Records[];                          //
  };                                         // Next 3*u_numRecords uints - actual linked list, i.e.
                                             // triplets of (pointer,depth,rgba).

//////////////////////////////////////////////////////////////////////////////////////////////

vec4 convert(uint rgba)
  {
  return vec4( float((rgba>>24u)&255u),float((rgba>>16u)&255u),float((rgba>>8u)&255u),float(rgba&255u) ) / 255.0;
  }

//////////////////////////////////////////////////////////////////////////////////////////////
// A over B (https://en.wikipedia.org/wiki/Alpha_compositing)

vec4 blend(vec4 A,vec4 B)
  {
  float b = B.a * (1.0-A.a);
  float a = A.a + b;

  return vec4( (A.rgb*A.a + B.rgb*b)/a , a );
  }

//////////////////////////////////////////////////////////////////////////////////////////////
// Pass4 of the OIT algorithm - keep traversing the linked list, build the final color and blend it.

void main()
  {
  uint prev = uint(v_Pixel.x) + uint(v_Pixel.y) * u_Size.x;
  uint curr = u_Records[prev];

  if (curr != 0u)
    {
    const float S= 2147483647.0;
    gl_FragDepth = 1.0 - 2.0*float(u_Records[curr+1u])/S;
    vec4 color   = convert(u_Records[curr+2u]);
    curr = u_Records[curr];

    while (curr != 0u)
      {
      color = blend( color , convert(u_Records[curr+2u]) );
      curr = u_Records[curr];
      }

    fragColor = color;
    }
  else discard;
}

Hi utumno,

Unfortunately due to the current circumstances I do not have access to an appropriate device to test your shaders.

Some educated guessing tells me that this is most likely due to an old driver bug that has been fixed on newer versions.

However I can help you come up with a work around for this. A potential culprit is the unbounded array in the SSBO (u_Records). You can start off by setting an appropriate size to this array that fits the worst case scenario and we can work from there.

Regards,
Dihara

Thanks Dihara, I’ll try that!

2 years ago I already reported the exact same bug, then affecting my HTC Desire 12 ( GE8100 with driver 1.8@4490469 ). So if you want to replicate maybe you could also try that. I have a feeling it affects alll GE8xxxx’s.

Here’s the original, 2 year old thread:

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