Module: wine Branch: master Commit: a50546e563efad3b25222ca965a2e52a83111d95 URL: http://source.winehq.org/git/wine.git/?a=commit;h=a50546e563efad3b25222ca965...
Author: Henri Verbeet hverbeet@codeweavers.com Date: Mon Jan 24 11:19:40 2011 +0100
wined3d: Use dot() instead of length() in shader_glsl_nrm().
As Eric Anholt pointed out, using length() here is suboptimal. It essentially translates into "inversesqrt(dot(x, x));", but needs to handle the case of zero-length vectors, much like nrm.
---
dlls/wined3d/glsl_shader.c | 8 +++++--- 1 files changed, 5 insertions(+), 3 deletions(-)
diff --git a/dlls/wined3d/glsl_shader.c b/dlls/wined3d/glsl_shader.c index a59e54b..c4e4188 100644 --- a/dlls/wined3d/glsl_shader.c +++ b/dlls/wined3d/glsl_shader.c @@ -2314,16 +2314,18 @@ static void shader_glsl_nrm(const struct wined3d_shader_instruction *ins) mask_size = shader_glsl_get_write_mask_size(write_mask); shader_glsl_add_src_param(ins, &ins->src[0], write_mask, &src_param);
- shader_addline(buffer, "tmp0.x = length(%s);\n", src_param.param_str); + shader_addline(buffer, "tmp0.x = dot(%s, %s);\n", + src_param.param_str, src_param.param_str); shader_glsl_append_dst(buffer, ins); + if (mask_size > 1) { - shader_addline(buffer, "tmp0.x == 0.0 ? vec%u(0.0) : (%s / tmp0.x));\n", + shader_addline(buffer, "tmp0.x == 0.0 ? vec%u(0.0) : (%s * inversesqrt(tmp0.x)));\n", mask_size, src_param.param_str); } else { - shader_addline(buffer, "tmp0.x == 0.0 ? 0.0 : (%s / tmp0.x));\n", + shader_addline(buffer, "tmp0.x == 0.0 ? 0.0 : (%s * inversesqrt(tmp0.x)));\n", src_param.param_str); } }