commit 699acd1602844d4290d8c12e874433db5cf1d01a
Author: Matt Low <matt@mlow.ca>
Date:   Fri Nov 13 18:46:31 2020 +0400

    Initial commit

diff --git a/.gitignore b/.gitignore
new file mode 100644
index 0000000..a81c8ee
--- /dev/null
+++ b/.gitignore
@@ -0,0 +1,138 @@
+# Byte-compiled / optimized / DLL files
+__pycache__/
+*.py[cod]
+*$py.class
+
+# C extensions
+*.so
+
+# Distribution / packaging
+.Python
+build/
+develop-eggs/
+dist/
+downloads/
+eggs/
+.eggs/
+lib/
+lib64/
+parts/
+sdist/
+var/
+wheels/
+share/python-wheels/
+*.egg-info/
+.installed.cfg
+*.egg
+MANIFEST
+
+# PyInstaller
+#  Usually these files are written by a python script from a template
+#  before PyInstaller builds the exe, so as to inject date/other infos into it.
+*.manifest
+*.spec
+
+# Installer logs
+pip-log.txt
+pip-delete-this-directory.txt
+
+# Unit test / coverage reports
+htmlcov/
+.tox/
+.nox/
+.coverage
+.coverage.*
+.cache
+nosetests.xml
+coverage.xml
+*.cover
+*.py,cover
+.hypothesis/
+.pytest_cache/
+cover/
+
+# Translations
+*.mo
+*.pot
+
+# Django stuff:
+*.log
+local_settings.py
+db.sqlite3
+db.sqlite3-journal
+
+# Flask stuff:
+instance/
+.webassets-cache
+
+# Scrapy stuff:
+.scrapy
+
+# Sphinx documentation
+docs/_build/
+
+# PyBuilder
+.pybuilder/
+target/
+
+# Jupyter Notebook
+.ipynb_checkpoints
+
+# IPython
+profile_default/
+ipython_config.py
+
+# pyenv
+#   For a library or package, you might want to ignore these files since the code is
+#   intended to run in multiple environments; otherwise, check them in:
+# .python-version
+
+# pipenv
+#   According to pypa/pipenv#598, it is recommended to include Pipfile.lock in version control.
+#   However, in case of collaboration, if having platform-specific dependencies or dependencies
+#   having no cross-platform support, pipenv may install dependencies that don't work, or not
+#   install all needed dependencies.
+#Pipfile.lock
+
+# PEP 582; used by e.g. github.com/David-OConnor/pyflow
+__pypackages__/
+
+# Celery stuff
+celerybeat-schedule
+celerybeat.pid
+
+# SageMath parsed files
+*.sage.py
+
+# Environments
+.env
+.venv
+env/
+venv/
+ENV/
+env.bak/
+venv.bak/
+
+# Spyder project settings
+.spyderproject
+.spyproject
+
+# Rope project settings
+.ropeproject
+
+# mkdocs documentation
+/site
+
+# mypy
+.mypy_cache/
+.dmypy.json
+dmypy.json
+
+# Pyre type checker
+.pyre/
+
+# pytype static type analyzer
+.pytype/
+
+# Cython debug symbols
+cython_debug/
diff --git a/geom.py b/geom.py
new file mode 100755
index 0000000..11d5213
--- /dev/null
+++ b/geom.py
@@ -0,0 +1,24 @@
+#!/usr/bin/env python
+import geom
+import pygame
+import sys
+
+def main():
+    pygame.init()
+    geom.init()
+
+    clock = pygame.time.Clock()
+    elapsed = 0
+    while geom.loop():
+        clock.tick(60)
+        #elapsed += clock.get_time()
+        #if elapsed >= 1000:
+        #    print(f"FPS: {clock.get_fps()}")
+        #    elapsed = 0
+
+    pygame.quit()
+    sys.exit()
+
+
+if __name__ == "__main__":
+    main()
diff --git a/geom/__init__.py b/geom/__init__.py
new file mode 100644
index 0000000..bd3a4d9
--- /dev/null
+++ b/geom/__init__.py
@@ -0,0 +1,34 @@
+import pygame
+from pygame.locals import *
+from . import text
+
+WIDTH = 1280
+HEIGHT = 720
+
+surface = None
+screen = None
+
+
+def init():
+    pygame.display.set_caption("Geom Demo")
+    pygame.mouse.set_visible(False)
+    global surface
+    global screen
+
+    surface = pygame.display.set_mode((WIDTH, HEIGHT))
+    text.init()
+
+    from .screen import Screen
+    screen = Screen()
+
+
+def loop():
+    for event in pygame.event.get(QUIT):
+        return False
+
+    surface.fill((0, 0, 0))
+
+    screen.render(surface)
+
+    pygame.display.update()
+    return True
diff --git a/geom/colors.py b/geom/colors.py
new file mode 100644
index 0000000..9744597
--- /dev/null
+++ b/geom/colors.py
@@ -0,0 +1,9 @@
+RED = (255, 0, 0, 255)
+YELLOW = (255, 255, 0, 255)
+GREEN = (0, 255, 0, 255)
+CYAN = (0, 255, 255, 255)
+BLUE = (0, 0, 255, 255)
+VIOLET = (255, 0, 255, 255)
+
+WHITE = (255, 255, 255, 255)
+BLACK = (0, 0, 0, 255)
diff --git a/geom/demos/aabb.py b/geom/demos/aabb.py
new file mode 100644
index 0000000..223d547
--- /dev/null
+++ b/geom/demos/aabb.py
@@ -0,0 +1,85 @@
+from pygame import draw, mouse
+from .. import text
+from ..geom.rect import Rect
+from .. import WIDTH, HEIGHT, text
+from ..colors import *
+from ..math import *
+
+class AABBDistance:
+
+    title = "AABB Distance"
+
+    def render(self, surface):
+        rect_a = Rect(
+            WIDTH / 2 - (WIDTH / 8),
+            HEIGHT / 2 - (HEIGHT / 8),
+            WIDTH / 4,
+            HEIGHT / 4,
+        )
+        rect_b = Rect(
+            *mouse.get_pos(),
+            WIDTH / 5,
+            HEIGHT / 5
+        )
+
+        # cx, cy = center
+        dist_x = abs(rect_b.cx - rect_a.cx)
+        dist_y = abs(rect_b.cy - rect_a.cy)
+
+        gap_x = dist_x - rect_a.halfwidth - rect_b.halfwidth
+        gap_y = dist_y - rect_a.halfheight - rect_b.halfheight
+
+        distance = 0
+
+        if gap_x < 0 and gap_y < 0:
+            distance = max(gap_x, gap_y)
+        else:
+            if gap_x < 0:
+                distance = gap_y
+            elif gap_y < 0:
+                distance = gap_x
+            else:
+                distance = length(gap_x, gap_y)
+
+        text.draw(surface, (10, HEIGHT - 20), WHITE, f"Distance: {distance}")
+        rect_a.draw(surface, YELLOW, 4)
+        rect_b.draw(surface, WHITE, 4)
+        draw.line(surface, RED if distance < 0 else GREEN,
+                  rect_a.get_center(), rect_b.get_center(), 2)
+
+class PointAABBDistance:
+
+    title = "Point-AABB Distance"
+
+    def render(self, surface):
+        rect_a = Rect(
+            WIDTH / 2 - (WIDTH / 8),
+            HEIGHT / 2 - (HEIGHT / 8),
+            WIDTH / 4,
+            HEIGHT / 4,
+        )
+        cx, cy = mouse.get_pos()
+
+        # cx, cy = point
+        dist_x = abs(cx - rect_a.cx)
+        dist_y = abs(cy - rect_a.cy)
+
+        gap_x = dist_x - rect_a.halfwidth
+        gap_y = dist_y - rect_a.halfheight
+
+        distance = 0
+
+        if gap_x < 0 and gap_y < 0:
+            distance = max(gap_x, gap_y)
+        else:
+            if gap_x < 0:
+                distance = gap_y
+            elif gap_y < 0:
+                distance = gap_x
+            else:
+                distance = length(gap_x, gap_y)
+
+        text.draw(surface, (10, HEIGHT - 20), WHITE, f"Distance: {distance}")
+        rect_a.draw(surface, YELLOW, 4)
+        draw.line(surface, RED if distance < 0 else GREEN,
+                  rect_a.get_center(), (cx, cy), 2)
diff --git a/geom/demos/vec_proj.py b/geom/demos/vec_proj.py
new file mode 100644
index 0000000..f4eadeb
--- /dev/null
+++ b/geom/demos/vec_proj.py
@@ -0,0 +1,29 @@
+from pygame import draw, mouse
+from .. import HEIGHT, WIDTH
+from ..colors import *
+from ..math import *
+
+class VecProj:
+
+    title = "Vector Projection"
+
+    def render(self, surface):
+        x1 = WIDTH / 4
+        y1 = HEIGHT / 2 + 100
+        x2 = 0.75 * WIDTH
+        y2 = HEIGHT / 2
+
+        cx, cy = mouse.get_pos()
+
+        lx, ly = x2 - x1, y2 - y1           # line vector
+        llen = length(lx, ly)
+        lnx, lny = lx / llen, ly / llen     # line normal
+        lcx, lcy = cx - x1, cy - y1         # line start - cursor vector
+
+        proj = dot(lcx, lcy, lx, ly) / llen
+
+        draw.line(
+            surface, GREEN, (cx, cy), add(x1, y1, *scale(lnx, lny, proj)), 5
+        )
+        draw.line(surface, WHITE, (cx, cy), (x1, y1), 5)
+        draw.line(surface, YELLOW, (x1, y1), (x2, y2), 5)
diff --git a/geom/geom/rect.py b/geom/geom/rect.py
new file mode 100644
index 0000000..a392f6f
--- /dev/null
+++ b/geom/geom/rect.py
@@ -0,0 +1,55 @@
+from pygame import draw, gfxdraw
+from pygame.rect import Rect as pRect
+
+class Rect:
+
+    def __init__(self, x, y, width, height):
+        self.x = x
+        self.y = y
+        self.height = height
+        self.width = width
+        self.update()
+
+    def update(self):
+        self.min_x = self.x
+        self.min_y = self.y
+        self.max_x = self.x + self.width
+        self.max_y = self.y + self.height
+
+        self.min = (self.min_x, self.min_y)
+        self.max = (self.max_x, self.max_y)
+
+        self.halfwidth = self.width / 2
+        self.halfheight = self.height / 2
+
+        self.cx = self.x + self.width / 2
+        self.cy = self.y + self.height / 2
+
+        self.vertices = [
+            (self.x, self.y),
+            (self.x + self.width, self.y),
+            (self.x + self.width, self.y + self.height),
+            (self.x, self.y + self.height)
+        ]
+        self.segments = [
+            (self.vertices[0], self.vertices[1]),
+            (self.vertices[1], self.vertices[2]),
+            (self.vertices[2], self.vertices[3]),
+            (self.vertices[3], self.vertices[0]),
+        ]
+
+    def get_center(self):
+        return (self.cx, self.cy)
+
+    def get_center_px(self):
+        return (int(self.cx), int(self.cy))
+
+    def contains(self, x, y):
+        return (x >= self.min_x and x <= self.max_x
+                and y >= self.min_y and y <= self.max_y)
+
+    def draw(self, surface, colour, width):
+        #gfxdraw.pixel(surface, *self.get_center_px(), colour)
+        draw.rect(surface, colour,
+                  pRect(self.x, self.y, self.width, self.height),
+                  width)
diff --git a/geom/math.py b/geom/math.py
new file mode 100644
index 0000000..98a2bee
--- /dev/null
+++ b/geom/math.py
@@ -0,0 +1,28 @@
+import math
+
+ZERO = (0, 0)
+
+def dot(x1, y1, x2, y2):
+    return (x1 * x2) + (y1 * y2)
+
+def length(x, y):
+    return math.sqrt((x * x) + (y * y))
+
+def normalize(x, y):
+    _len = length(x, y)
+    return x / _len, y / _len
+
+def scale(x, y, factor):
+    return x * factor, y * factor
+
+def add(x1, y1, x2, y2):
+    return x1 + x2, y1 + y2
+
+def sub(x1, y1, x2, y2):
+    return x1 - x2, y1 - y2
+
+def vmin(x1, y1, x2, y2):
+    return min(x1, x2), min(y1, y2)
+
+def vmax(x1, y1, x2, y2):
+    return max(x1, x2), max(y1, y2)
diff --git a/geom/screen.py b/geom/screen.py
new file mode 100644
index 0000000..d56c299
--- /dev/null
+++ b/geom/screen.py
@@ -0,0 +1,40 @@
+import pygame
+from .demos import aabb, vec_proj
+from . import text, HEIGHT
+from .colors import *
+
+class Screen:
+
+    def __init__(self):
+        self.demos = [
+            vec_proj.VecProj(),
+            aabb.AABBDistance(),
+            aabb.PointAABBDistance(),
+        ]
+        self.demo = 0
+
+    def handle_input(self):
+        for event in pygame.event.get(pygame.KEYDOWN):
+            if event.key == pygame.K_DOWN:
+                self.demo += 1
+                if self.demo >= len(self.demos):
+                    self.demo = 0
+            elif event.key == pygame.K_UP:
+                self.demo -= 1
+                if self.demo < 0:
+                    self.demo = len(self.demos) - 1
+
+    def draw_demo_list(self, surface):
+        y_offset = 10
+        for i in range(len(self.demos)):
+            text.draw(surface,
+                      (10, y_offset + i * 20),
+                      CYAN if self.demo == i else WHITE,
+                      self.demos[i].title)
+
+    def render(self, surface):
+        self.handle_input()
+
+        self.demos[self.demo].render(surface)
+
+        self.draw_demo_list(surface)
diff --git a/geom/text.py b/geom/text.py
new file mode 100644
index 0000000..735bb35
--- /dev/null
+++ b/geom/text.py
@@ -0,0 +1,10 @@
+from pygame import freetype
+
+FONT = None
+
+def init():
+    global FONT
+    FONT = freetype.SysFont('Arial', 16)
+
+def draw(surface, position, color, text):
+    FONT.render_to(surface, position, text, color)
diff --git a/requirements.txt b/requirements.txt
new file mode 100644
index 0000000..88d1df8
--- /dev/null
+++ b/requirements.txt
@@ -0,0 +1 @@
+pygame==2.0.0