Method draw

dgl/src/OpenGL3.cpp:119–150

template<typename T>
void Line<T>::draw(const GraphicsContext& context, const T width)
{
    DISTRHO_SAFE_ASSERT_RETURN(width != 0,);

    const OpenGL3GraphicsContext& gl3context = static_cast<const OpenGL3GraphicsContext&>(context);

    if (gl3context.program == 0)
        return;

    const GLfloat x1 = (static_cast<double>(posStart.x) / gl3context.width) * 2 - 1;
    const GLfloat y1 = (static_cast<double>(posStart.y) / gl3context.height) * -2 + 1;
    const GLfloat x2 = (static_cast<double>(posEnd.x) / gl3context.width) * 2 - 1;
    const GLfloat y2 = (static_cast<double>(posEnd.y) / gl3context.height) * -2 + 1;

    glLineWidth(static_cast<GLfloat>(width));

    const GLfloat vertices[] = { x1, y1, x2, y2, };
    glBindBuffer(GL_ARRAY_BUFFER, gl3context.buffers[0]);
    glBufferData(GL_ARRAY_BUFFER, sizeof(vertices), vertices, GL_STREAM_DRAW);
    glEnableVertexAttribArray(gl3context.bounds);
    glVertexAttribPointer(gl3context.bounds, 2, GL_FLOAT, GL_FALSE, 0, nullptr);

    const GLubyte order[] = { 0, 1 };
    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, gl3context.buffers[1]);
    glBufferData(GL_ELEMENT_ARRAY_BUFFER, sizeof(order), order, GL_STATIC_DRAW);

    glDrawElements(GL_LINES, ARRAY_SIZE(order), GL_UNSIGNED_BYTE, nullptr);

    glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
    glDisableVertexAttribArray(gl3context.bounds);
    glBindBuffer(GL_ARRAY_BUFFER, 0);
}

#ifdef DGL_ALLOW_DEPRECATED_METHODS
template<typename T>