Implement GL_MAX_PROGRAM_TEXEL_OFFSET and GL_MAX_TEXTURE_LOD_BIAS

- GL_MAX_PROGRAM_TEXEL_OFFSET and GL_MIN_PROGRAM_TEXEL_OFFSET were
  technically already properly implemented, since the spec mentions
  that the behavior outside of these limits is undefined, and
  SwiftShader has no actual hard limit for these parameters.
- GL_MAX_TEXTURE_LOD_BIAS also has no hard limit in SwiftShader,
  other than the limit imposed on LOD itself, so that limit was
  used for GL_MAX_TEXTURE_LOD_BIAS.

Change-Id: I60b15b7f7a0febbc3e6582caff6c6a414a5d4964
Reviewed-on: https://swiftshader-review.googlesource.com/11709
Reviewed-by: Nicolas Capens <nicolascapens@google.com>
Tested-by: Alexis Hétu <sugoi@google.com>

diff --git a/src/Main/Config.hpp b/src/Main/Config.hpp
index 7a754f3..b9256ea 100644 (file)
--- a/src/Main/Config.hpp
+++ b/src/Main/Config.hpp
@@ -98,6 +98,7 @@ namespace sw
                MAX_TRANSFORM_FEEDBACK_INTERLEAVED_COMPONENTS = 64,
                MIN_PROGRAM_TEXEL_OFFSET = -8,
                MAX_PROGRAM_TEXEL_OFFSET = 7,
+               MAX_TEXTURE_LOD = MIPMAP_LEVELS - 2,   // Trilinear accesses lod+1
                RENDERTARGETS = 8,
        };
 }

diff --git a/src/OpenGL/libGLESv2/Context.cpp b/src/OpenGL/libGLESv2/Context.cpp
index 3cd11af..6ca3c81 100644 (file)
--- a/src/OpenGL/libGLESv2/Context.cpp
+++ b/src/OpenGL/libGLESv2/Context.cpp
@@ -2178,15 +2178,18 @@ template<typename T> bool Context::getIntegerv(GLenum pname, T *params) const
                        *params = MAX_FRAGMENT_UNIFORM_COMPONENTS;
                        return true;
                case GL_MAX_PROGRAM_TEXEL_OFFSET:
-                       UNIMPLEMENTED();
+                       // Note: SwiftShader has no actual texel offset limit, so this limit can be modified if required.
+                       // In any case, any behavior outside the specified range is valid since the spec mentions:
+                       // (see OpenGL ES 3.0.5, 3.8.10.1 Scale Factor and Level of Detail, p.153)\r                     // "If any of the offset values are outside the range of the  implementation-defined values
+                       //  MIN_PROGRAM_TEXEL_OFFSET and MAX_PROGRAM_TEXEL_OFFSET, results of the texture lookup are
+                       //  undefined."
                        *params = MAX_PROGRAM_TEXEL_OFFSET;
                        return true;
                case GL_MAX_SERVER_WAIT_TIMEOUT:
                        *params = 0;
                        return true;
                case GL_MAX_TEXTURE_LOD_BIAS:
-                       UNIMPLEMENTED();
-                       *params = 2;
+                       *params = MAX_TEXTURE_LOD_BIAS;
                        return true;
                case GL_MAX_TRANSFORM_FEEDBACK_INTERLEAVED_COMPONENTS:
                        *params = sw::MAX_TRANSFORM_FEEDBACK_INTERLEAVED_COMPONENTS;
@@ -2216,7 +2219,11 @@ template<typename T> bool Context::getIntegerv(GLenum pname, T *params) const
                        *params = MAX_VERTEX_UNIFORM_COMPONENTS;
                        return true;
                case GL_MIN_PROGRAM_TEXEL_OFFSET:
-                       UNIMPLEMENTED();
+                       // Note: SwiftShader has no actual texel offset limit, so this limit can be modified if required.
+                       // In any case, any behavior outside the specified range is valid since the spec mentions:
+                       // (see OpenGL ES 3.0.5, 3.8.10.1 Scale Factor and Level of Detail, p.153)\r                     // "If any of the offset values are outside the range of the  implementation-defined values
+                       //  MIN_PROGRAM_TEXEL_OFFSET and MAX_PROGRAM_TEXEL_OFFSET, results of the texture lookup are
+                       //  undefined."
                        *params = MIN_PROGRAM_TEXEL_OFFSET;
                        return true;
                case GL_MINOR_VERSION:

diff --git a/src/OpenGL/libGLESv2/Context.h b/src/OpenGL/libGLESv2/Context.h
index 16e0aa2..d00f545 100644 (file)
--- a/src/OpenGL/libGLESv2/Context.h
+++ b/src/OpenGL/libGLESv2/Context.h
@@ -88,6 +88,7 @@ enum
        MAX_FRAGMENT_INPUT_VECTORS = 15,
        MIN_PROGRAM_TEXEL_OFFSET = sw::MIN_PROGRAM_TEXEL_OFFSET,
        MAX_PROGRAM_TEXEL_OFFSET = sw::MAX_PROGRAM_TEXEL_OFFSET,
+       MAX_TEXTURE_LOD_BIAS = sw::MAX_TEXTURE_LOD,
        MAX_DRAW_BUFFERS = sw::RENDERTARGETS,
        MAX_COLOR_ATTACHMENTS = MAX(MAX_DRAW_BUFFERS, 8),
        MAX_FRAGMENT_UNIFORM_BLOCKS = sw::MAX_FRAGMENT_UNIFORM_BLOCKS,

diff --git a/src/Renderer/Sampler.cpp b/src/Renderer/Sampler.cpp
index 24734da..60f5e35 100644 (file)
--- a/src/Renderer/Sampler.cpp
+++ b/src/Renderer/Sampler.cpp
@@ -72,7 +72,7 @@ namespace sw
 
                texture.baseLevel = 0;
                texture.maxLevel = 1000;
-               texture.maxLod = MIPMAP_LEVELS - 2;     // Trilinear accesses lod+1
+               texture.maxLod = MAX_TEXTURE_LOD;
                texture.minLod = 0;
        }
 
@@ -344,12 +344,12 @@ namespace sw
 
        void Sampler::setMinLod(float minLod)
        {
-               texture.minLod = clamp(minLod, 0.0f, (float)(MIPMAP_LEVELS - 2));
+               texture.minLod = clamp(minLod, 0.0f, (float)(MAX_TEXTURE_LOD));
        }
 
        void Sampler::setMaxLod(float maxLod)
        {
-               texture.maxLod = clamp(maxLod, 0.0f, (float)(MIPMAP_LEVELS - 2));
+               texture.maxLod = clamp(maxLod, 0.0f, (float)(MAX_TEXTURE_LOD));
        }
 
        void Sampler::setFilterQuality(FilterType maximumFilterQuality)