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#include "graphics.h"
#include <cmath>
#include <vector>
struct Vec3 {
float x, y, z;
};
// Rotate point around X axis
Vec3 rotateX(const Vec3& v, float angle) {
float c = std::cos(angle);
float s = std::sin(angle);
return {
v.x,
v.y * c - v.z * s,
v.y * s + v.z * c
};
}
// Rotate point around Y axis
Vec3 rotateY(const Vec3& v, float angle) {
float c = std::cos(angle);
float s = std::sin(angle);
return {
v.x * c + v.z * s,
v.y,
-v.x * s + v.z * c
};
}
// Perspective projection
void project(const Vec3& v, int& x2d, int& y2d, float width, float height) {
float distance = 2.0f; // camera distance
float scale = 100.0f; // zoom factor
float z = v.z + distance;
float factor = scale / z;
x2d = static_cast<int>(v.x * factor + width / 2);
y2d = static_cast<int>(v.y * factor + height / 2);
}
int main() {
const int width = 640;
const int height = 480;
WindowHandle* window = createWindow("3D Spinning Cube", width, height);
if (!window) return -1;
// Cube vertices
std::vector<Vec3> vertices = {
{-1, -1, -1},
{ 1, -1, -1},
{ 1, 1, -1},
{-1, 1, -1},
{-1, -1, 1},
{ 1, -1, 1},
{ 1, 1, 1},
{-1, 1, 1}
};
// Cube edges (pairs of vertex indices)
std::vector<std::pair<int,int>> edges = {
{0,1},{1,2},{2,3},{3,0}, // back face
{4,5},{5,6},{6,7},{7,4}, // front face
{0,4},{1,5},{2,6},{3,7} // connecting edges
};
float angle = 0.0f;
while (!windowShouldClose(window)) {
pollEvents(window);
clearScreen(window, Color(0, 0, 0)); // RGB 20, 20, 30
std::vector<Vec3> transformed;
// Rotate cube
for (const auto& v : vertices) {
Vec3 r = rotateX(v, angle);
r = rotateY(r, angle * 0.7f);
transformed.push_back(r);
}
// Draw edges
for (const auto& edge : edges) {
int x1, y1, x2, y2;
project(transformed[edge.first], x1, y1, width, height);
project(transformed[edge.second], x2, y2, width, height);
drawLine(window, x1, y1, x2, y2, Color(255, 255, 255)); // RGB 0 255 180
}
swapBuffers(window);
angle += 0.01f;
delay(16); // ~60 FPS
}
destroyWindow(window);
return 0;
}
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