diff --git a/examples/others/raymath_vector_angle.c b/examples/others/raymath_vector_angle.c new file mode 100644 index 000000000..86cd91a93 --- /dev/null +++ b/examples/others/raymath_vector_angle.c @@ -0,0 +1,106 @@ +/******************************************************************************************* +* +* raylib [shapes] example - Vector Angle +* +* Example originally created with raylib 1.0, last time updated with raylib 4.2 +* +* 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 = { 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 + //---------------------------------------------------------------------------------- + if (IsKeyPressed(KEY_SPACE)) angleMode = !angleMode; + + if (angleMode == 0) + { + // Calculate angle between two vectors, considering a common origin (v0) + v1 = Vector2Add(v0, (Vector2){ 100.0f, 80.0f }); + v2 = GetMousePosition(); + angle = Vector2Angle(Vector2Normalize(Vector2Subtract(v1, v0)), Vector2Normalize(Vector2Subtract(v2, v0)))*RAD2DEG; + } + else if (angleMode == 1) + { + // Calculate angle defined by a two vectors line, in reference to horizontal line + v1 = (Vector2){ screenWidth/2, screenHeight/2 }; + v2 = GetMousePosition(); + angle = Vector2LineAngle(v1, v2)*RAD2DEG; + } + //---------------------------------------------------------------------------------- + + // Draw + //---------------------------------------------------------------------------------- + BeginDrawing(); + + ClearBackground(RAYWHITE); + + if (angleMode == 0) DrawText("v0", v0.x, v0.y, 10, DARKGRAY); + DrawText("v1", v1.x, v1.y, 10, DARKGRAY); + DrawText("v2", v2.x, v2.y, 10, DARKGRAY); + + if (angleMode == 0) + { + DrawText("MODE: Angle between V1 and V2", 10, 10, 20, BLACK); + + DrawLineEx(v0, v1, 2.0f, BLACK); + DrawLineEx(v0, v2, 2.0f, RED); + + // TODO: Properly draw circle sector + DrawCircleSector(v0, 40.0f, Vector2LineAngle(v0, v1)*RAD2DEG, angle, 32, Fade(GREEN, 0.6f)); + } + else if (angleMode == 1) + { + DrawText("MODE: Angle formed by line V1 to V2", 10, 10, 20, BLACK); + + DrawLine(0, screenHeight/2, screenWidth, screenHeight/2, LIGHTGRAY); + DrawLineEx(v1, v2, 2.0f, RED); + + DrawCircleSector(v1, 40.0f, 90.0f, 180 - angle - 90, 32, Fade(GREEN, 0.6f)); + } + + DrawText("Press SPACE to change MODE", 460, 10, 20, DARKGRAY); + DrawText(TextFormat("ANGLE: %2.2f", angle), 10, 40, 20, LIME); + + EndDrawing(); + //---------------------------------------------------------------------------------- + } + + // De-Initialization + //-------------------------------------------------------------------------------------- + CloseWindow(); // Close window and OpenGL context + //-------------------------------------------------------------------------------------- + + return 0; +} diff --git a/examples/others/raymath_vector_angle.png b/examples/others/raymath_vector_angle.png new file mode 100644 index 000000000..29995e002 Binary files /dev/null and b/examples/others/raymath_vector_angle.png differ diff --git a/src/raymath.h b/src/raymath.h index 47728ff69..6a929cf6e 100644 --- a/src/raymath.h +++ b/src/raymath.h @@ -314,8 +314,19 @@ RMAPI float Vector2DistanceSqr(Vector2 v1, Vector2 v2) // NOTE: Angle is calculated from origin point (0, 0) RMAPI float Vector2Angle(Vector2 v1, Vector2 v2) { - float result = atan2f(v2.y - v1.y, v2.x - v1.x); + float result = 0.0f; + + float dot = v1.x*v2.x + v1.y*v2.y; // Dot product + float dotClamp = (dot < -1.0f)? -1.0f : dot; // Clamp + if (dotClamp > 1.0f) dotClamp = 1.0f; + result = acosf(dotClamp); + + // Alternative implementation, more costly + //float v1Length = sqrtf((v1.x*v1.x) + (v1.y*v1.y)); + //float v2Length = sqrtf((v2.x*v2.x) + (v2.y*v2.y)); + //float result = -acosf((v1.x*v2.x + v1.y*v2.y)/(v1Length*v2Length)); + return result; } @@ -325,18 +336,8 @@ RMAPI float Vector2Angle(Vector2 v1, Vector2 v2) RMAPI float Vector2LineAngle(Vector2 start, Vector2 end) { float result = 0.0f; - - float dot = start.x*end.x + start.y*end.y; // Dot product - - float dotClamp = (dot < -1.0f)? -1.0f : dot; // Clamp - if (dotClamp > 1.0f) dotClamp = 1.0f; - - result = acosf(dotClamp); - - // Alternative implementation, more costly - //float v1Length = sqrtf((start.x*start.x) + (start.y*start.y)); - //float v2Length = sqrtf((end.x*end.x) + (end.y*end.y)); - //float result = -acosf((start.x*end.x + start.y*end.y)/(v1Length*v2Length)); + + result = atan2f(end.y - start.y, end.x - start.x); return result; }