Add physics demo

Author: GregChan

examples/physics/demo.py

@@ -0,0 +1,92 @@
+"""
+raylib [physac] example - physics demo
+"""
+
+from pyray import Vector2
+from raylib import *
+from raylib.colors import (
+    BLACK,
+    GREEN,
+    WHITE
+)
+
+SCREEN_WIDTH = 800
+SCREEN_HEIGHT = 450
+
+SetConfigFlags(FLAG_MSAA_4X_HINT)
+InitWindow(SCREEN_WIDTH, SCREEN_HEIGHT, b'[physac] Basic demo')
+
+InitPhysics()
+
+floor = CreatePhysicsBodyRectangle(Vector2(SCREEN_WIDTH/2, SCREEN_HEIGHT), 500, 100, 10)
+floor.enabled = False
+
+circle = CreatePhysicsBodyCircle(Vector2(SCREEN_WIDTH/2, SCREEN_HEIGHT/2), 45, 10)
+circle.enabled = False
+
+SetTargetFPS(60)
+
+while not WindowShouldClose():
+    # Update
+    # ----------------------------------------------------------------------
+    UpdatePhysics()  # Update physics system
+
+    if IsKeyPressed(KEY_R):  # Reset physics system
+        ResetPhysics()
+
+        floor = CreatePhysicsBodyRectangle(Vector2(SCREEN_WIDTH/2, SCREEN_HEIGHT), 500, 100, 10)
+        floor.enabled = False
+
+        circle = CreatePhysicsBodyCircle(Vector2(SCREEN_WIDTH/2, SCREEN_HEIGHT/2), 45, 10)
+        circle.enabled = False
+
+    # Physics body creation inputs
+    if IsMouseButtonPressed(MOUSE_BUTTON_LEFT):
+        CreatePhysicsBodyPolygon(GetMousePosition(), GetRandomValue(20, 80), GetRandomValue(3, 8), 10)
+    elif IsMouseButtonPressed(MOUSE_BUTTON_RIGHT):
+        CreatePhysicsBodyCircle(GetMousePosition(), GetRandomValue(10, 45), 10)
+
+    # Destroy falling physics bodies
+    bodies_count = GetPhysicsBodiesCount()
+    for i in reversed(range(bodies_count)):
+        body = GetPhysicsBody(i)
+
+        if body and body.position.y > SCREEN_HEIGHT * 2:
+            DestroyPhysicsBody(body)
+    # ----------------------------------------------------------------------
+
+    # Draw
+    # ----------------------------------------------------------------------
+    BeginDrawing()
+
+    ClearBackground(BLACK)
+    DrawFPS(SCREEN_WIDTH - 90, SCREEN_HEIGHT - 30)
+
+    # Draw created physics bodies
+    bodies_count = GetPhysicsBodiesCount()
+    for i in range(bodies_count):
+        body = GetPhysicsBody(i)
+
+        if body:
+            vertex_count = GetPhysicsShapeVerticesCount(i)
+            for j in range(vertex_count):
+                # Get physics bodies shape vertices to draw lines
+                # Note: GetPhysicsShapeVertex() already calculates rotation transformations
+                vertexA = GetPhysicsShapeVertex(body, j)
+
+                # Get next vertex or first to close the shape
+                jj = (j + 1) if (j+1) < vertex_count else 0
+                vertexB = GetPhysicsShapeVertex(body, jj)
+
+                # Draw a line between two vertex positions
+                DrawLineV(vertexA, vertexB, GREEN)
+
+    DrawText(b'Left mouse button to create a polygon', 10, 10, 10, WHITE)
+    DrawText(b'Right mouse button to create a circle', 10, 25, 10, WHITE)
+    DrawText(b"Press 'R' to reset example", 10, 40, 10, WHITE)
+
+    EndDrawing()
+    # ----------------------------------------------------------------------
+
+ClosePhysics()
+CloseWindow()