raylib/examples/others/raymath_vector_angle.c

123 lines
4.9 KiB
C

/*******************************************************************************************
*
* raylib [shapes] example - Vector Angle
*
* Example originally created with raylib 1.0, last time updated with raylib 4.6
*
* Example licensed under an unmodified zlib/libpng license, which is an OSI-certified,
* BSD-like license that allows static linking with closed source software
*
* Copyright (c) 2023 Ramon Santamaria (@raysan5)
*
********************************************************************************************/
#include "raylib.h"
#include "raymath.h"
//------------------------------------------------------------------------------------
// Program main entry point
//------------------------------------------------------------------------------------
int main(void)
{
// Initialization
//--------------------------------------------------------------------------------------
const int screenWidth = 800;
const int screenHeight = 450;
InitWindow(screenWidth, screenHeight, "raylib [math] example - vector angle");
Vector2 v0 = { screenWidth/2, screenHeight/2 };
Vector2 v1 = Vector2Add(v0, (Vector2){ 100.0f, 80.0f });
Vector2 v2 = { 0 }; // Updated with mouse position
float angle = 0.0f; // Angle in degrees
int angleMode = 0; // 0-Vector2Angle(), 1-Vector2LineAngle()
SetTargetFPS(60); // Set our game to run at 60 frames-per-second
//--------------------------------------------------------------------------------------
// Main game loop
while (!WindowShouldClose()) // Detect window close button or ESC key
{
// Update
//----------------------------------------------------------------------------------
float startangle = 0.0f;
if (angleMode == 0) startangle = -Vector2LineAngle(v0, v1)*RAD2DEG;
if (angleMode == 1) startangle = 0.0f;
v2 = GetMousePosition();
if (IsKeyPressed(KEY_SPACE)) angleMode = !angleMode;
if(angleMode == 0 && IsMouseButtonDown(MOUSE_BUTTON_RIGHT)) v1 = GetMousePosition();
if (angleMode == 0)
{
// Calculate angle between two vectors, considering a common origin (v0)
Vector2 v1Normal = Vector2Normalize(Vector2Subtract(v1, v0));
Vector2 v2Normal = Vector2Normalize(Vector2Subtract(v2, v0));
angle = Vector2Angle(v1Normal, v2Normal)*RAD2DEG;
}
else if (angleMode == 1)
{
// Calculate angle defined by a two vectors line, in reference to horizontal line
angle = Vector2LineAngle(v0, v2)*RAD2DEG;
}
//----------------------------------------------------------------------------------
// Draw
//----------------------------------------------------------------------------------
BeginDrawing();
ClearBackground(RAYWHITE);
if (angleMode == 0)
{
DrawText("MODE 0: Angle between V1 and V2", 10, 10, 20, BLACK);
DrawText("Right Click to Move V2", 10, 30, 20, DARKGRAY);
DrawLineEx(v0, v1, 2.0f, BLACK);
DrawLineEx(v0, v2, 2.0f, RED);
DrawCircleSector(v0, 40.0f, startangle, startangle + angle, 32, Fade(GREEN, 0.6f));
}
else if (angleMode == 1)
{
DrawText("MODE 1: Angle formed by line V1 to V2", 10, 10, 20, BLACK);
DrawLine(0, screenHeight/2, screenWidth, screenHeight/2, LIGHTGRAY);
DrawLineEx(v0, v2, 2.0f, RED);
DrawCircleSector(v0, 40.0f, startangle, startangle - angle, 32, Fade(GREEN, 0.6f));
}
DrawText("v0", v0.x, v0.y, 10, DARKGRAY);
// If the line from v0 to v1 would overlap the text, move it's position up 10
if (angleMode == 0 && Vector2Subtract(v0, v1).y > 0.0f) DrawText("v1", v1.x, v1.y-10.0f, 10, DARKGRAY);
if (angleMode == 0 && Vector2Subtract(v0, v1).y < 0.0f) DrawText("v1", v1.x, v1.y, 10, DARKGRAY);
// If angle mode 1, use v1 to emphasize the horizontal line
if (angleMode == 1) DrawText("v1", v0.x + 40.0f, v0.y, 10, DARKGRAY);
// position adjusted by -10 so it isn't hidden by cursor
DrawText("v2", v2.x-10.0f, v2.y-10.0f, 10, DARKGRAY);
DrawText("Press SPACE to change MODE", 460, 10, 20, DARKGRAY);
DrawText(TextFormat("ANGLE: %2.2f", angle), 10, 70, 20, LIME);
EndDrawing();
//----------------------------------------------------------------------------------
}
// De-Initialization
//--------------------------------------------------------------------------------------
CloseWindow(); // Close window and OpenGL context
//--------------------------------------------------------------------------------------
return 0;
}