diff options
| -rw-r--r-- | src/glsl/ir_constant_expression.cpp | 16 | 
1 files changed, 15 insertions, 1 deletions
| diff --git a/src/glsl/ir_constant_expression.cpp b/src/glsl/ir_constant_expression.cpp index a2748a726c..b6cb2d8672 100644 --- a/src/glsl/ir_constant_expression.cpp +++ b/src/glsl/ir_constant_expression.cpp @@ -1064,7 +1064,21 @@ ir_call::constant_expression_value()        for (unsigned c = 0; c < op[0]->type->components(); c++)  	 data.f[c] = sinhf(op[0]->value.f[c]);     } else if (strcmp(callee, "smoothstep") == 0) { -      return NULL; /* FINISHME: implement this */ +      assert(num_parameters == 3); +      assert(op[1]->type == op[0]->type); +      unsigned edge_inc = op[0]->type->is_scalar() ? 0 : 1; +      for (unsigned c = 0, e = 0; c < type->components(); e += edge_inc, c++) { +	 const float edge0 = op[0]->value.f[e]; +	 const float edge1 = op[1]->value.f[e]; +	 if (edge0 == edge1) { +	    data.f[c] = 0.0; /* Avoid a crash - results are undefined anyway */ +	 } else { +	    const float numerator = op[2]->value.f[c] - edge0; +	    const float denominator = edge1 - edge0; +	    const float t = CLAMP(numerator/denominator, 0, 1); +	    data.f[c] = t * t * (3 - 2 * t); +	 } +      }     } else if (strcmp(callee, "sqrt") == 0) {        expr = new(mem_ctx) ir_expression(ir_unop_sqrt, type, op[0], NULL);     } else if (strcmp(callee, "step") == 0) { | 
