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-rw-r--r--src/misc.zig171
1 files changed, 171 insertions, 0 deletions
diff --git a/src/misc.zig b/src/misc.zig
index 6f1d893..d523827 100644
--- a/src/misc.zig
+++ b/src/misc.zig
@@ -377,6 +377,177 @@ pub fn saveScores(base_dir: []const u8, current: Scores) !void {
try dir.writeFile("scores.ini", data);
}
+export fn getFrustum(frustum: [*][4]f32) void {
+ var proj: [16]f32 = undefined;
+ c.glGetFloatv(c.GL_PROJECTION_MATRIX, &proj);
+
+ var mv: [16]f32 = undefined;
+ c.glGetFloatv(c.GL_MODELVIEW_MATRIX, &mv);
+
+ const clip = [16]f32{
+ mv[0] * proj[0] + mv[1] * proj[4] + mv[2] * proj[8] + mv[3] * proj[12],
+ mv[0] * proj[1] + mv[1] * proj[5] + mv[2] * proj[9] + mv[3] * proj[13],
+ mv[0] * proj[2] + mv[1] * proj[6] + mv[2] * proj[10] + mv[3] * proj[14],
+ mv[0] * proj[3] + mv[1] * proj[7] + mv[2] * proj[11] + mv[3] * proj[15],
+ mv[4] * proj[0] + mv[5] * proj[4] + mv[6] * proj[8] + mv[7] * proj[12],
+ mv[4] * proj[1] + mv[5] * proj[5] + mv[6] * proj[9] + mv[7] * proj[13],
+ mv[4] * proj[2] + mv[5] * proj[6] + mv[6] * proj[10] + mv[7] * proj[14],
+ mv[4] * proj[3] + mv[5] * proj[7] + mv[6] * proj[11] + mv[7] * proj[15],
+ mv[8] * proj[0] + mv[9] * proj[4] + mv[10] * proj[8] + mv[11] * proj[12],
+ mv[8] * proj[1] + mv[9] * proj[5] + mv[10] * proj[9] + mv[11] * proj[13],
+ mv[8] * proj[2] + mv[9] * proj[6] + mv[10] * proj[10] + mv[11] * proj[14],
+ mv[8] * proj[3] + mv[9] * proj[7] + mv[10] * proj[11] + mv[11] * proj[15],
+ mv[12] * proj[0] + mv[13] * proj[4] + mv[14] * proj[8] + mv[15] * proj[12],
+ mv[12] * proj[1] + mv[13] * proj[5] + mv[14] * proj[9] + mv[15] * proj[13],
+ mv[12] * proj[2] + mv[13] * proj[6] + mv[14] * proj[10] + mv[15] * proj[14],
+ mv[12] * proj[3] + mv[13] * proj[7] + mv[14] * proj[11] + mv[15] * proj[15],
+ };
+
+ // Right plane
+ frustum[0][0] = clip[3] - clip[0];
+ frustum[0][1] = clip[7] - clip[4];
+ frustum[0][2] = clip[11] - clip[8];
+ frustum[0][3] = clip[15] - clip[12];
+
+ // Left plane
+ frustum[1][0] = clip[3] + clip[0];
+ frustum[1][1] = clip[7] + clip[4];
+ frustum[1][2] = clip[11] + clip[8];
+ frustum[1][3] = clip[15] + clip[12];
+
+ // Bottom plane
+ frustum[2][0] = clip[3] + clip[1];
+ frustum[2][1] = clip[7] + clip[5];
+ frustum[2][2] = clip[11] + clip[9];
+ frustum[2][3] = clip[15] + clip[13];
+
+ // Top plane
+ frustum[3][0] = clip[3] - clip[1];
+ frustum[3][1] = clip[7] - clip[5];
+ frustum[3][2] = clip[11] - clip[9];
+ frustum[3][3] = clip[15] - clip[13];
+
+ // Far plane
+ frustum[4][0] = clip[3] - clip[2];
+ frustum[4][1] = clip[7] - clip[6];
+ frustum[4][2] = clip[11] - clip[10];
+ frustum[4][3] = clip[15] - clip[14];
+
+ // Near plane
+ frustum[5][0] = clip[3] + clip[2];
+ frustum[5][1] = clip[7] + clip[6];
+ frustum[5][2] = clip[11] + clip[10];
+ frustum[5][3] = clip[15] + clip[14];
+
+ // normalize the right plane
+ var t: f32 = undefined;
+ t = @sqrt(frustum[0][0]*frustum[0][0]
+ + frustum[0][1]*frustum[0][1]
+ + frustum[0][2]*frustum[0][2]);
+ frustum[0][0] /= t;
+ frustum[0][1] /= t;
+ frustum[0][2] /= t;
+ frustum[0][3] /= t;
+
+ // calculate left plane
+ frustum[1][0] = clip[3] + clip[0];
+ frustum[1][1] = clip[7] + clip[4];
+ frustum[1][2] = clip[11] + clip[ 8];
+ frustum[1][3] = clip[15] + clip[12];
+
+ // normalize the left plane
+ t = @sqrt(frustum[1][0]*frustum[1][0]
+ + frustum[1][1]*frustum[1][1]
+ + frustum[1][2]*frustum[1][2]);
+ frustum[1][0] /= t;
+ frustum[1][1] /= t;
+ frustum[1][2] /= t;
+ frustum[1][3] /= t;
+
+ // calculate the bottom plane
+ frustum[2][0] = clip[3] + clip[1];
+ frustum[2][1] = clip[7] + clip[5];
+ frustum[2][2] = clip[11] + clip[9];
+ frustum[2][3] = clip[15] + clip[13];
+
+ // normalize the bottom plane
+ t = @sqrt(frustum[2][0]*frustum[2][0]
+ + frustum[2][1]*frustum[2][1]
+ + frustum[2][2]*frustum[2][2]);
+ frustum[2][0] /= t;
+ frustum[2][1] /= t;
+ frustum[2][2] /= t;
+ frustum[2][3] /= t;
+
+ // calculate the top plane
+ frustum[3][0] = clip[3] - clip[1];
+ frustum[3][1] = clip[7] - clip[5];
+ frustum[3][2] = clip[11] - clip[9];
+ frustum[3][3] = clip[15] - clip[13];
+
+ // normalize the top plane
+ t = @sqrt(frustum[3][0]*frustum[3][0]
+ + frustum[3][1]*frustum[3][1]
+ + frustum[3][2]*frustum[3][2]);
+ frustum[3][0] /= t;
+ frustum[3][1] /= t;
+ frustum[3][2] /= t;
+ frustum[3][3] /= t;
+
+ // calculate the far plane
+ frustum[4][0] = clip[3] - clip[2];
+ frustum[4][1] = clip[7] - clip[6];
+ frustum[4][2] = clip[11] - clip[10];
+ frustum[4][3] = clip[15] - clip[14];
+
+ // normalize the far plane
+ t = @sqrt(frustum[4][0]*frustum[4][0]
+ + frustum[4][1]*frustum[4][1]
+ + frustum[4][2]*frustum[4][2]);
+ frustum[4][0] /= t;
+ frustum[4][1] /= t;
+ frustum[4][2] /= t;
+ frustum[4][3] /= t;
+
+ // calculate the near plane
+ frustum[5][0] = clip[3] + clip[2];
+ frustum[5][1] = clip[7] + clip[6];
+ frustum[5][2] = clip[11] + clip[10];
+ frustum[5][3] = clip[15] + clip[14];
+
+ // normalize the near plane
+ t = @sqrt(frustum[5][0]*frustum[5][0]
+ + frustum[5][1]*frustum[5][1]
+ + frustum[5][2]*frustum[5][2]);
+ frustum[5][0] /= t;
+ frustum[5][1] /= t;
+ frustum[5][2] /= t;
+ frustum[5][3] /= t;
+}
+
+export fn cubeInFrustum(frustum: [*][4]f32,
+ x: f32, y: f32, z: f32, size: f32) bool {
+ const delta = [_]f32{ -size, size };
+ var i = @as(u8, 0);
+ loop: while (i < 6) : (i += 1) {
+ for (delta) |dx| for (delta) |dy| for (delta) |dz|
+ if (frustum[i][0] * (x + dx) + frustum[i][1] * (y + dy)
+ + frustum[i][2] * (z + dz) + frustum[i][3] > 0) continue :loop;
+ return false;
+ }
+ return true;
+}
+
+export fn sphereInFrustum(frustum: [*][4]f32,
+ x: f32, y: f32, z: f32, r: f32) bool {
+ var i = @as(u8, 0);
+ while (i < 6) : (i += 1)
+ if (frustum[i][0] * x + frustum[i][1] * y
+ + frustum[i][2] * z + frustum[i][3] <= -r)
+ return false;
+ return true;
+}
+
const Text = struct {
texture: u32,
base: u32,
generated by cgit v1.2.3 (git 2.25.1) at 2026-01-27 09:52:22 +0000