Function DemoCustomPerPointStyle

implot3d_demo.cpp:1630–1744

}

void DemoCustomPerPointStyle() {
    IMGUI_DEMO_MARKER("Custom/Custom Per-Point Style");
    ImGui::BulletText("Demonstrates per-point coloring using colormap sampling.");
    ImGui::BulletText("A different color is sampled for each point.");
    ImGui::BulletText("All points share the same label for a single legend entry.");

    static float marker_size = 4.0f;
    static ImPlot3DColormap cmap = ImPlot3DColormap_Viridis;

    ImGui::SliderFloat("Marker Size", &marker_size, 2.0f, 10.0f);
    if (ImGui::BeginCombo("Colormap", ImPlot3D::GetColormapName(cmap))) {
        ImPlot3DContext& gp = *GImPlot3D;
        for (int i = 0; i < ImPlot3D::GetColormapCount(); i++) {
            // Only show continuous colormaps
            if (!gp.ColormapData.IsQual(i)) {
                if (ImGui::Selectable(ImPlot3D::GetColormapName(i), cmap == i))
                    cmap = i;
            }
        }
        ImGui::EndCombo();
    }

    // Generate three stacked toruses with different color patterns
    static float torus_data[3][400][4]; // 3 toruses, 400 points each, XYZT per point
    static bool initialized = false;
    if (!initialized) {
        const float R = 0.6f; // Major radius
        const float r = 0.2f; // Minor radius
        const int u_samples = 20;
        const int v_samples = 20;

        for (int torus = 0; torus < 3; torus++) {
            float z_offset = (2 - torus) * 0.6f;
            int idx = 0;

            for (int i = 0; i < u_samples; i++) {
                float u = (float)i / u_samples * 2.0f * IM_PI;
                for (int j = 0; j < v_samples; j++) {
                    float v = (float)j / v_samples * 2.0f * IM_PI;

                    // Parametric torus equations
                    float x = (R + r * ImCos(v)) * ImCos(u);
                    float y = (R + r * ImCos(v)) * ImSin(u);
                    float z = r * ImSin(v) + z_offset;

                    // Different color pattern for each torus
                    float t;
                    if (torus == 0) {
                        // Color by height (Z coordinate)
                        // Normalize Z to [0, 1] range for this torus
                        t = (z - (z_offset - r)) / (2.0f * r);
                    } else if (torus == 1) {
                        // Color by radial distance from tube center
                        // V parameter directly gives us position around tube
                        // Map from [-r, +r] to [0, 1]
                        t = (ImCos(v) + 1.0f) / 2.0f;
                    } else {
                        // Angular pattern: varies smoothly around the major circle