Mesa (master): main: round floating-point value to nearest integer in glGetTexParameteriv()

[Iago Toral Quiroga]

Module: Mesa
Branch: master
Commit: d8d59202af1d409ad2e10c2893612ff6fa05d3a2
URL:    http://cgit.freedesktop.org/mesa/mesa/commit/?id=d8d59202af1d409ad2e10c2893612ff6fa05d3a2

Author: Samuel Iglesias Gonsalvez <siglesias at igalia.com>
Date:   Thu Dec 11 23:34:14 2014 +0100

main: round floating-point value to nearest integer in glGetTexParameteriv()

Previously, a cast was done to convert from float to int but there
were rounding errors.

The spec specificies in Data Conversion chapter that Floating-point values are
rounded to the nearest integer.

This patch fixes the following 8 dEQP tests:

dEQP-GLES3.functional.state_query.texture.texture_2d_texture_min_lod_gettexparameteri
dEQP-GLES3.functional.state_query.texture.texture_2d_texture_max_lod_gettexparameteri
dEQP-GLES3.functional.state_query.texture.texture_3d_texture_min_lod_gettexparameteri
dEQP-GLES3.functional.state_query.texture.texture_3d_texture_max_lod_gettexparameteri
dEQP-GLES3.functional.state_query.texture.texture_2d_array_texture_min_lod_gettexparameteri
dEQP-GLES3.functional.state_query.texture.texture_2d_array_texture_max_lod_gettexparameteri
dEQP-GLES3.functional.state_query.texture.texture_cube_map_texture_min_lod_gettexparameteri
dEQP-GLES3.functional.state_query.texture.texture_cube_map_texture_max_lod_gettexparameteri

Signed-off-by: Samuel Iglesias Gonsalvez <siglesias at igalia.com>
Reviewed-by: Ian Romanick <ian.d.romanick at intel.com>

---

 src/mesa/main/texparam.c |   17 ++++++++++++-----
 1 file changed, 12 insertions(+), 5 deletions(-)

diff --git a/src/mesa/main/texparam.c b/src/mesa/main/texparam.c
index 772e699..c4a5841 100644
--- a/src/mesa/main/texparam.c
+++ b/src/mesa/main/texparam.c
@@ -1957,14 +1957,18 @@ get_tex_parameteriv(struct gl_context *ctx,
       case GL_TEXTURE_MIN_LOD:
          if (!_mesa_is_desktop_gl(ctx) && !_mesa_is_gles3(ctx))
             goto invalid_pname;
-
-         *params = (GLint) obj->Sampler.MinLod;
+         /* GL spec 'Data Conversions' section specifies that floating-point
+          * value in integer Get function is rounded to nearest integer
+          */
+         *params = IROUND(obj->Sampler.MinLod);
          break;
       case GL_TEXTURE_MAX_LOD:
          if (!_mesa_is_desktop_gl(ctx) && !_mesa_is_gles3(ctx))
             goto invalid_pname;
-
-         *params = (GLint) obj->Sampler.MaxLod;
+         /* GL spec 'Data Conversions' section specifies that floating-point
+          * value in integer Get function is rounded to nearest integer
+          */
+         *params = IROUND(obj->Sampler.MaxLod);
          break;
       case GL_TEXTURE_BASE_LEVEL:
          if (!_mesa_is_desktop_gl(ctx) && !_mesa_is_gles3(ctx))
@@ -1978,7 +1982,10 @@ get_tex_parameteriv(struct gl_context *ctx,
       case GL_TEXTURE_MAX_ANISOTROPY_EXT:
          if (!ctx->Extensions.EXT_texture_filter_anisotropic)
             goto invalid_pname;
-         *params = (GLint) obj->Sampler.MaxAnisotropy;
+         /* GL spec 'Data Conversions' section specifies that floating-point
+          * value in integer Get function is rounded to nearest integer
+          */
+         *params = IROUND(obj->Sampler.MaxAnisotropy);
          break;
       case GL_GENERATE_MIPMAP_SGIS:
          if (ctx->API != API_OPENGL_COMPAT && ctx->API != API_OPENGLES)