commit 5e331bc8752bbe6362289283b2c7d6d86d0c8fe7 Author: Leszek Koltunski Date: Sun Jul 1 23:07:36 2018 +0100 Update the 'main' shaders for OIT. diff --git a/src/main/res/raw/main_fragment_shader.glsl b/src/main/res/raw/main_fragment_shader.glsl index 084f7f5..60999f1 100644 --- a/src/main/res/raw/main_fragment_shader.glsl +++ b/src/main/res/raw/main_fragment_shader.glsl @@ -19,23 +19,31 @@ precision highp float; -#if __VERSION__ != 100 in vec3 v_Position; // Interpolated position for this fragment. in vec3 v_Normal; // Interpolated normal for this fragment. in vec2 v_TexCoordinate; // Interpolated texture coordinate per fragment. + out vec4 fragColor; // The output color -#define TEXTURE texture -#define FRAG_COLOR fragColor -#else -varying vec3 v_Position; // Interpolated position for this fragment. -varying vec3 v_Normal; // Interpolated normal for this fragment. -varying vec2 v_TexCoordinate; // Interpolated texture coordinate per fragment. -#define TEXTURE texture2D -#define FRAG_COLOR gl_FragColor -#endif uniform sampler2D u_Texture; // The input texture. +#ifdef OIT +////////////////////////////////////////////////////////////////////////////////////////////// +// per-pixel linked list. Order Independent Transparency. + +in vec2 v_Pixel; // location of the current fragment, in pixels +uniform uvec2 u_Size; +uniform uint u_numRecords; + +layout (binding=0, offset=0) uniform atomic_uint u_Counter; + +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). +#endif + #if NUM_FRAGMENT>0 uniform int fNumEffects; // total number of fragment effects uniform int fName[NUM_FRAGMENT]; // their namess. @@ -43,11 +51,55 @@ uniform vec4 fUniforms[2*NUM_FRAGMENT]; // i-th effect is 2 consecutive vec4's: // next describes the Region, i.e. area over which the effect is active. #endif // NUM_FRAGMENT>0 +#ifdef OIT +////////////////////////////////////////////////////////////////////////////////////////////// +// Concurrent insert to a linked list. Tim Harris, 'pragmatic implementation of non-blocking +// linked-lists', 2001. +// This arranges fragments by decreasing 'depth', so one would think - from back to front, but +// in main() below the depth is mapped with S*(1-depth)/2, so it is really front to back. + +void insert( vec2 ij, uint depth, uint rgba ) + { + uint ptr = atomicCounterIncrement(u_Counter); + + if( ptr u_Records[curr+1u] ) // need to insert here + { + u_Records[ptr] = curr; // next of new record is curr + memoryBarrier(); + uint res = atomicCompSwap( u_Records[prev], curr, ptr ); + + if (res==curr) break; // done! + else curr = res; // could not insert! retry from same place in list + } + else // advance in list + { + prev = curr; + curr = u_Records[prev]; + } + } + } + } +#endif // OIT + ////////////////////////////////////////////////////////////////////////////////////////////// void main() { - vec4 color = TEXTURE(u_Texture,v_TexCoordinate); + vec4 color = texture(u_Texture,v_TexCoordinate); #if NUM_FRAGMENT>0 vec2 diff; @@ -65,5 +117,21 @@ void main() } #endif - FRAG_COLOR = vec4(color.rgb * (1.0 + 7.0*v_Normal.z) * 0.125, color.a); +#ifdef OIT + if( frag.a > 0.95 ) + { + fragColor= vec4(color.rgb * (1.0 + 7.0*v_Normal.z) * 0.125, color.a); + } + else + { + if( frag.a > 0.0 ) + { + const float S= 2147483647.0; // max signed int. Could probably be max unsigned int but this is enough. + insert(v_Pixel, uint(S*(1.0-depth)/2.0), convert(frag) ); + } + discard; + } +#else + fragColor = vec4(color.rgb * (1.0 + 7.0*v_Normal.z) * 0.125, color.a); +#endif } \ No newline at end of file diff --git a/src/main/res/raw/main_vertex_shader.glsl b/src/main/res/raw/main_vertex_shader.glsl index 78f2267..0b7f689 100644 --- a/src/main/res/raw/main_vertex_shader.glsl +++ b/src/main/res/raw/main_vertex_shader.glsl @@ -19,7 +19,6 @@ precision highp float; -#if __VERSION__ != 100 in vec3 a_Position; // Per-vertex position. in vec3 a_Normal; // Per-vertex normal vector. in vec2 a_TexCoordinate; // Per-vertex texture coordinate. @@ -27,14 +26,10 @@ out vec3 v_Position; // out vec3 v_endPosition; // for Transform Feedback only out vec3 v_Normal; // out vec2 v_TexCoordinate; // -#else -attribute vec3 a_Position; // Per-vertex position. -attribute vec3 a_Normal; // Per-vertex normal vector. -attribute vec2 a_TexCoordinate; // Per-vertex texture coordinate. -varying vec3 v_Position; // -varying vec3 v_endPosition; // for Transform Feedback only -varying vec3 v_Normal; // -varying vec2 v_TexCoordinate; // + +#ifdef OIT +out vec2 v_Pixel; // 2D pixel coords in window space +uniform uvec2 u_Size; // size of the output surface, in pixels. #endif uniform vec3 u_objD; // half of object width x half of object height X half the depth; @@ -165,6 +160,11 @@ void main() #endif v_Position = v; + +#ifdef OIT + v_Pixel = (a_Position.xy + 0.5) * vec2(u_Size); +#endif + v_endPosition = v + (0.3*u_objD.x)*n; v_TexCoordinate = a_TexCoordinate; v_Normal = normalize(vec3(u_MVMatrix*vec4(n,0.0)));