LibGfx+LibGL: Allow singular matrices to be inverted

This is basically the old behavior before the GLtron port was
introduced, but `.inverse()` no longer crashes if the matrix is
singular.
This commit is contained in:
Jelle Raaijmakers 2022-01-12 00:54:14 +01:00 committed by Linus Groh
parent b2e0bf24ef
commit a41d5ffa1e
Notes: sideshowbarker 2024-07-17 21:09:00 +09:00
2 changed files with 5 additions and 12 deletions

View file

@ -317,8 +317,7 @@ void SoftwareGLContext::gl_end()
mv_elements[0][0], mv_elements[1][0], mv_elements[2][0],
mv_elements[0][1], mv_elements[1][1], mv_elements[2][1],
mv_elements[0][2], mv_elements[1][2], mv_elements[2][2]);
auto normal_transform_or_error = model_view_transposed.inverse();
auto const& normal_transform = normal_transform_or_error.is_error() ? model_view_transposed : normal_transform_or_error.release_value();
auto const& normal_transform = model_view_transposed.inverse();
m_rasterizer.draw_primitives(primitive_type, m_model_view_matrix, normal_transform, m_projection_matrix, m_texture_matrix, m_vertex_list, enabled_texture_units);
@ -2810,9 +2809,7 @@ void SoftwareGLContext::gl_tex_gen_floatv(GLenum coord, GLenum pname, GLfloat co
texture_coordinate_generation(capability).object_plane_coefficients = { params[0], params[1], params[2], params[3] };
break;
case GL_EYE_PLANE: {
auto inverse_matrix_or_error = m_model_view_matrix.inverse();
auto const& inverse_model_view_matrix = inverse_matrix_or_error.is_error() ? m_model_view_matrix : inverse_matrix_or_error.release_value();
auto const& inverse_model_view = m_model_view_matrix.inverse();
auto input_coefficients = FloatVector4 { params[0], params[1], params[2], params[3] };
// Note: we are allowed to store transformed coefficients here, according to the documentation on
@ -2821,7 +2818,7 @@ void SoftwareGLContext::gl_tex_gen_floatv(GLenum coord, GLenum pname, GLfloat co
// "The returned values are those maintained in eye coordinates. They are not equal to the values
// specified using glTexGen, unless the modelview matrix was identity when glTexGen was called."
texture_coordinate_generation(capability).eye_plane_coefficients = inverse_model_view_matrix * input_coefficients;
texture_coordinate_generation(capability).eye_plane_coefficients = inverse_model_view * input_coefficients;
break;
}
default:

View file

@ -6,7 +6,6 @@
#pragma once
#include <AK/Error.h>
#include <AK/Types.h>
#include <initializer_list>
@ -159,12 +158,9 @@ public:
return result;
}
[[nodiscard]] constexpr ErrorOr<Matrix> inverse() const
[[nodiscard]] constexpr Matrix inverse() const
{
auto det = determinant();
if (det == 0)
return Error::from_string_literal("inverse of matrix does not exist"sv);
return adjugate() / det;
return adjugate() / determinant();
}
[[nodiscard]] constexpr Matrix transpose() const