Before this commit, inserting into BSP tree could easily overflow
the stack because we allocate very large stack frames and, on
convex geometries (e.g. a sphere), the BSP tree degenerates into
a "BSP list", thus requiring one large stack frame per triangle.
This can be reproduced by exporting a 2d shaded view of sphere.
After this commit, the stack frames only contan a pointer to
a supplementary data structure, and moreover it only allocates
its fields on demand, conserving heap memory as well.
As a side effect, an arbitrary classifier limit of 50 vertices
is removed.
SurfaceRenderer is a new renderer implementing the Canvas interface
running entirely on the CPU; it projects strokes and triangles
in the exact same way as OpenGL would, and it can be used for
rendering into raster or vector 2d surfaces.
This has several desirable consequences:
* It is now possible to port SolveSpace to a later version of
OpenGL, such as OpenGLES 2, so that it runs on platforms that
only have that OpenGL version;
* The majority of geometry is now rendered without references to
the camera in C++ code, so a renderer can now submit it to
the video card once and re-rasterize with a different projection
matrix every time the projection is changed, avoiding expensive
reuploads;
* The DOGD (draw or get distance) interface is now
a straightforward Canvas implementation;
* There are no more direct references to SS.GW.(projection)
in sketch rendering code, which allows rendering to multiple
viewports;
* There are no more unnecessary framebuffer flips on CPU on Cocoa
and GTK;
* The platform-dependent GL code is now confined to rendergl1.cpp.
* The Microsoft and Apple headers required by it that are prone to
identifier conflicts are no longer included globally;
* The rendergl1.cpp implementation can now be omitted from
compilation to run SolveSpace headless or with a different
OpenGL version.
Note these implementation details of Canvas:
* GetCamera currently always returns a reference to the field
`Camera camera;`. This is so that a future renderer that caches
geometry in the video memory can define it as asserting, which
would provide assurance against code that could accidentally
put something projection-dependent in the cache;
* Line and triangle rendering is specified through a level of
indirection, hStroke and hFill. This is so that a future renderer
that batches geometry could cheaply group identical styles.
* DrawPixmap and DrawVectorText accept a (o,u,v) and not a matrix.
This is so that a future renderer into an output format that
uses 2d transforms (e.g. SVG) could easily derive those.
Some additional internal changes were required to enable this:
* Pixmap is now always passed as std::shared_ptr<{const ,}Pixmap>.
This is so that the renderer could cache uploaded textures
between API calls, which requires it to capture a (weak)
reference.
* The PlatformPathEqual function was properly extracted into
platform-specific code. This is so that the <windows.h> header
could be included only where needed (in platform/w32* as well
as rendergl1.cpp).
* The SBsp{2,3}::DebugDraw functions were removed. They can be
rewritten using the Canvas API if they are ever needed.
While no visual changes were originally intended, some minor fixes
happened anyway:
* The "emphasis" yellow line from top-left corner is now correctly
rendered much wider.
* The marquee rectangle is now pixel grid aligned.
* The hidden entities now do not clobber the depth buffer, removing
some minor artifacts.
* The workplane "tab" now scales with the font used to render
the workplane name.
* The workplane name font is now taken from the normals style.
* Workplane and constraint line stipple is insignificantly
different. This is so that it can reuse the existing stipple
codepaths; rendering of workplanes and constraints predates
those.
Some debug functionality was added:
* In graphics window, an fps counter that becomes red when
rendering under 60fps is drawn.
This is to ensure that:
* it is clear, when looking at the point of usage, what is
the purpose of "true" or "false";
* when refactoring, a simple search will bring up any places that
need to be changed.
Also, argument names were synchronized between declaration and
implementation.
As an exception, these are not annotated:
* Printf(/*halfLine=*/), to avoid pointless churn.
Specifically, this enables -Wswitch=error on GCC/Clang and its MSVC
equivalent; the exact way it is handled varies slightly, but what
they all have in common is that in a switch statement over an
enumeration, any enumerand that is not explicitly (via case:) or
implicitly (via default:) handled in the switch triggers an error.
Moreover, we also change the switch statements in three ways:
* Switch statements that ought to be extended every time a new
enumerand is added (e.g. Entity::DrawOrGetDistance(), are changed
to explicitly list every single enumerand, and not have a
default: branch.
Note that the assertions are kept because it is legal for
a enumeration to have a value unlike any of its defined
enumerands, and we can e.g. read garbage from a file, or
an uninitialized variable. This requires some rearranging if
a default: branch is undesired.
* Switch statements that ought to only ever see a few select
enumerands, are changed to always assert in the default: branch.
* Switch statements that do something meaningful for a few
enumerands, and ignore everything else, are changed to do nothing
in a default: branch, under the assumption that changing them
every time an enumerand is added or removed would just result
in noise and catch no bugs.
This commit also removes the {Request,Entity,Constraint}::UNKNOWN and
Entity::DATUM_POINT enumerands, as those were just fancy names for
zeroes. They mess up switch exhaustiveness checks and most of the time
were not the best way to implement what they did anyway.
Specifically, take the old code that looks like this:
class Foo {
enum { X = 1, Y = 2 };
int kind;
}
... foo.kind = Foo::X; ...
and convert it to this:
class Foo {
enum class Kind : uint32_t { X = 1, Y = 2 };
Kind kind;
}
... foo.kind = Foo::Kind::X;
(In some cases the enumeration would not be in the class namespace,
such as when it is generally useful.)
The benefits are as follows:
* The type of the field gives a clear indication of intent, both
to humans and tools (such as binding generators).
* The compiler is able to automatically warn when a switch is not
exhaustive; but this is currently suppressed by the
default: ssassert(false, ...)
idiom.
* Integers and plain enums are weakly type checked: they implicitly
convert into each other. This can hide bugs where type conversion
is performed but not intended. Enum classes are strongly type
checked.
* Plain enums pollute parent namespaces; enum classes do not.
Almost every defined enum we have already has a kind of ad-hoc
namespacing via `NAMESPACE_`, which is now explicit.
* Plain enums do not have a well-defined ABI size, which is
important for bindings. Enum classes can have it, if specified.
We specify the base type for all enums as uint32_t, which is
a safe choice and allows us to not change the numeric values
of any variants.
This commit introduces absolutely no functional change to the code,
just renaming and change of types. It handles almost all cases,
except GraphicsWindow::pending.operation, which needs minor
functional change.
This will allow us in future to accept `const T &` anywhere it's
necessary to reduce the amount of copying.
This commit is quite conservative: it does not attempt very hard to
refactor code that performs incidental mutation. In particular
dogd and caches are not marked with the `mutable` keyword.
dogd will be eliminated later, opening up more opportunities to
add const qualifiers.
This commit also doesn't introduce any uses of the newly added const
qualifers. This will be done later.
This includes explanation and context for non-obvious cases and
shortens debug cycles when just-in-time debugging is not available
(like on Linux) by immediately printing description of the assert
as well as symbolized backtrace.
According to the C++ standard, "this" is never NULL, so checks
of the form "if(!this)" can be legally optimized out. This
breaks SolveSpace on GCC 6, and probably on other compilers and
configurations.
This will allow us to use non-POD classes inside these objects
in future and is otherwise functionally equivalent, as well
as more concise.
Note that there are some subtleties with handling of
brace-initialization. Specifically:
On aggregates (e.g. simple C-style structures) using an empty
brace-initializer zero-initializes the aggregate, i.e. it makes
all members zero.
On non-aggregates an empty brace-initializer calls the default
constructor. And if the constructor doesn't explicitly initialize
the members (which the auto-generated constructor doesn't) then
the members will be constructed but otherwise uninitialized.
So, what is an aggregate class? To quote the C++ standard
(C++03 8.5.1 §1):
An aggregate is an array or a class (clause 9) with no
user-declared constructors (12.1), no private or protected
non-static data members (clause 11), no base classes (clause 10),
and no virtual functions (10.3).
In SolveSpace, we only have to handle the case of base classes;
Constraint and Entity have those. Thus, they had to gain a default
constructor that does nothing but initializes the members to zero.
The main benefit is that std::swap will ensure that the type
of arguments is copy-constructible and move-constructible.
It is more concise as well.
When min and max are defined as macros, they will conflict
with STL header files included by other C++ libraries;
in this case STL will #undef any other definition.
However, don't use ssglLineWidth for UI drawing operations.
These only draw horizontal or vertical lines that don't need to
be antialiased, and thus don't require the workaround. In fact
the workaround would make them thicker than needed.
The SolveSpace top-level directory was getting a bit cluttered, so
following the example of numerous other free-software projects, we move the
main application source into a subdirectory and adjust the build systems
accordingly.
Also, got rid of the obj/ directory in favor of creating it on the fly in
Makefile.msvc.
