From 54b35e673596d767a13f06f4d7ec1089e18fd46e Mon Sep 17 00:00:00 2001 From: Kenneth Graunke <kenneth@whitecape.org> Date: Wed, 1 Sep 2010 15:37:13 -0700 Subject: glsl: Add proper handling for constant matrix-from-matrix constructors. Fixes piglit test case constructor-21.vert and changes constructor-22.vert to give the correct output. --- src/glsl/ir.cpp | 25 +++++++++++++++++++++++++ 1 file changed, 25 insertions(+) (limited to 'src') diff --git a/src/glsl/ir.cpp b/src/glsl/ir.cpp index aee44a77c95..68ad512bf50 100644 --- a/src/glsl/ir.cpp +++ b/src/glsl/ir.cpp @@ -450,6 +450,31 @@ ir_constant::ir_constant(const struct glsl_type *type, exec_list *value_list) return; } + if (type->is_matrix() && value->type->is_matrix()) { + assert(value->next->is_tail_sentinel()); + + /* From section 5.4.2 of the GLSL 1.20 spec: + * "If a matrix is constructed from a matrix, then each component + * (column i, row j) in the result that has a corresponding component + * (column i, row j) in the argument will be initialized from there." + */ + unsigned cols = MIN2(type->matrix_columns, value->type->matrix_columns); + unsigned rows = MIN2(type->vector_elements, value->type->vector_elements); + for (unsigned i = 0; i < cols; i++) { + for (unsigned j = 0; j < rows; j++) { + const unsigned src = i * value->type->vector_elements + j; + const unsigned dst = i * type->vector_elements + j; + this->value.f[dst] = value->value.f[src]; + } + } + + /* "All other components will be initialized to the identity matrix." */ + for (unsigned i = cols; i < type->matrix_columns; i++) + this->value.f[i * type->vector_elements + i] = 1.0; + + return; + } + /* Use each component from each entry in the value_list to initialize one * component of the constant being constructed. */ -- cgit v1.2.3