From 04b3643dbf2e0d25e67c86845b2506ad1d26939d Mon Sep 17 00:00:00 2001 From: Kenneth Graunke Date: Wed, 21 Jul 2010 20:33:42 -0700 Subject: ir_constant_expression: Add support for the "refract" builtin. --- src/glsl/ir_constant_expression.cpp | 12 +++++++++++- 1 file changed, 11 insertions(+), 1 deletion(-) (limited to 'src/glsl/ir_constant_expression.cpp') diff --git a/src/glsl/ir_constant_expression.cpp b/src/glsl/ir_constant_expression.cpp index c8320814a3..580ef1d4fa 100644 --- a/src/glsl/ir_constant_expression.cpp +++ b/src/glsl/ir_constant_expression.cpp @@ -1018,7 +1018,17 @@ ir_call::constant_expression_value() for (unsigned c = 0; c < op[0]->type->components(); c++) data.f[c] = op[0]->value.f[c] - 2 * dot_NI * op[1]->value.f[c]; } else if (strcmp(callee, "refract") == 0) { - return NULL; /* FINISHME: implement this */ + const float eta = op[2]->value.f[0]; + const float dot_NI = dot(op[1], op[0]); + const float k = 1.0 - eta * eta * (1.0 - dot_NI * dot_NI); + if (k < 0.0) { + return ir_constant::zero(mem_ctx, this->type); + } else { + for (unsigned c = 0; c < type->components(); c++) { + data.f[c] = eta * op[0]->value.f[c] - (eta * dot_NI + sqrtf(k)) + * op[1]->value.f[c]; + } + } } else if (strcmp(callee, "sign") == 0) { expr = new(mem_ctx) ir_expression(ir_unop_sign, type, op[0], NULL); } else if (strcmp(callee, "sin") == 0) { -- cgit v1.2.3