v1.3.4: Color changes, rendering improvements, bug fixes

This release includes a number of small changes from the last 15 months, including:

• Dutch translation, thanks to Vistaus
• AppStream metadata, thanks to Mailaender
• sRGB-correct color rendering, to make shading and fog look a bit more realistic. Some maps' colors have been adjusted slightly to compensate.
• Percentage-closer filtering is now used, producing less jagged shadows.
• Object transforms are now applied in the vertex shader, which reduces CPU usage slightly
• Map wall/tile fragments are now drawn only once; this reduces GPU usage

I only sporadically work on Trackballs, and make releases when some amount of time or code has accumulated. If you want me to make a release earlier for any reason, please ask. If you have bug reports (or wish to report that a level is too easy/too hard), please file an issue here on Github.

v1.3.3: A few bug fixes

This release includes a few minor bug fixes from the last 9 months, including:

• Trackballs now can more reliably be built when multiple versions of GNU Guile are installed
• Fixed a bug where the default difficulty setting sometimes was not remembered
• Text shown in game should now always be UTF-8, making accents display properly even when running Trackballs from the "C" locale
• A clarification that the source code and assets are available under "GPL v2 or later", except for the music, some of which has a different license.

I only sporadically work on Trackballs, and make releases when some amount of time or code has accumulated. If you want me to make a release earlier for any reason, please ask. If you have bug reports (or wish to report that a level is too easy/too hard), please file an issue here on Github.

Many small changes

This release includes a number of small changes from the last one and a half years. Notable are:

• Making the game logic more deterministic
• Slightly adjusting the dizziness mechanic
• Making Trackballs buildable with Guile 3.0, and fixing a few compiler warnings
• Drawing objects with Blinn-Phong shading, instead of Phong
• Balls are now rendered more accurately
• The level editor now visually displays cell flags (poison, trampoline effect, etc.)

I only sporadically work on Trackballs, and make releases when some amount of time or code has accumulated. If you want me to make a release earlier for any reason, please ask. If you have bug reports (or wish to report that a level is too easy/too hard), please file an issue here on Github.

Have fun!

Bugfixes, cleanup, speedups, lighting, etc.

Along with bug fixes and performance improvements this release adjusts
the fragment shaders to avoid oversaturated/clipped colors.

Changes include:

• CMakeLists fix to install paths for icons and documentation (see issue #15)
• Callbacks are delayed until the end of the physics tick
• Updated manpage
• Reduced image loading and memory use on startup
• Minor difficulty adjustments to fourSeasons_4, ds3, con4.
• Build is now reproducible (thanks to #17)

Enjoy!

Ball physics symmetrization

This release includes a significant modification of the ball physics code,
mainly replacing existing heuristics for the interaction of the ball and the
map with more symmetric and general ones. Note that the physics is by no
means realistic.

Those building Trackballs should take note of changes to install path handling
options in CMakeLists.txt.

Changes include but are not limited to:

• Jump handling reworked; no more double jumping, and rolling off edges
  behaves consistently if not always as expected. (The ball can acquire a sort of
  internal downward, but not upward, "momentum".) One can no longer jump
  out of acid.
• Physics code runs somewhat slower than before.
• Ball controls made more consistent, and more rotation invariant; Shift key no
  longer accelerates the ball slightly, but rather slows it down.
• Nitro modpill forces maximum acceleration, instead of acting as a
  controllable speed boost.
• Level set adjustments to compensate for physics changes
• Added a new levelset which more fully uses the scripting API.
• Settings include time acceleration; Sandbox mode is unavailable by default.

Enjoy!

More uniform interface and a new help screen

In addition to bug fixes and level script adjustments, Trackballs has

• A bit less lag when there are >100 balls present
• Menu fonts that scale to match the window size
• A fully redesigned help mode
• Complete (if mediocre) German and French translations

Enjoy!

A bunch of minor improvements

Among which

• Now using a vector graphics icon
• Tab key navigation for menu items -- no mouse required
• Translatable strings no longer have leading/trailing whitespace
• Moving objects are updated at the game physics rate

Enjoy!

Cascaded shadows and speedups

Bringing several minor bugfixes, but also:

• Cascaded shadow maps for day mode lighting
• CMake build script now properly checks for project dependencies
• Map editor indicates trigger locations
• Reflection processing is much faster (if you're CPU (not GPU) limited, that is)

Enjoy!

Improved rendering and guile api

The most important changes from this minor release:

• Levelset API updated so that entity coordinates are now integers at cell centers
• Point shadow rendering introduced, although it's currently rather slow
• Restored ball reflections broken in v1.2.0
• Map editor can load the initial positions of objects from the script file

The list of systems on which I've been able to build trackballs now includes one
with Guile 2.0.0 and SDL 2.0.0, which are the minimum program requirements.
The OpenGL requirement has been adjusted to at least version 3.3, where it will
stay for the foreseeable future.

Enjoy!

Updated trackballs

Since trackballs 1.1.4, this update features:

• Updated dependencies. Now based on SDL2 (c. 2013), Guile 2.0 (c. 2011), OpenGL 3.1 core (c. 2010)
• Made windows resizeable
• Extended the domain of translations to include level maps
• Config/highscore files are now human-readable
• Level scripting errors don't crash the main program
• Build system uses CMake (still a few things left to adjust)
• Improved object clipping

I have verified that the program builds on 64-bit Linux with the current
latest releases of SDL (2.05), Guile (2.2.2), gettext 0.19.8.1, and an OpenGL 4.5
capable GPU. As I lack access to older (but not ancient) systems. I can't
guarantee where Trackballs will compile and run. If it doesn't, please file
an issue so I can fix the problem.

See also https://trackballs.github.io/ for more documentation.