DrawLine in native extension

Questions
#1

I am working on new native extension(3d physics) and i need to draw lines to make debug draw.
How can i do that?
1)I can export points to lua. And call msg.post("@render:",“draw_line”,{…})
I don’t like that way,it will create a lot of new objects every frame. Not gc friendly:(
2)Post message to render from c++.

    dmGameObject::HInstance instance = dmScript::CheckGOInstance(L);
    dmRenderDDF::DrawLine msg;
    dmMessage::Result result = dmMessage::PostDDF(&msg,0x0, &url,
        (uintptr_t) instance,0, 0);
    if(result!=dmMessage::RESULT_OK){
         dmLogError("can't draw line");
    }

But i don’t understand how to get url to render
3.You have physics_debug_render

This render call dmRender::Line3D and dmRender::Triangle3d.
Maybe i also can call this functions in my native extension?

Thanks. I will be happy for any help)

4 Likes
#2

It worked :partying_face:
Post draw_line messages to render in c++.

#include "static_hash.h"
#include "objects/debug_renderer_userdata.h"
#include "utils.h"
#include <render/render_ddf.h> // dmRenderDDF::DrawLine
namespace dmRender
{
    extern const char* RENDER_SOCKET_NAME;
}

namespace dmMessage
{
    Result GetSocket(const char *name, HSocket* out_socket);
}

using namespace reactphysics3d;

namespace rp3dDefold {

inline void RGBUintToVector(uint rgb, dmVMath::Vector4 &color){
    color.setX(((rgb & 0x00FF0000) >> 16)/256.0);
    color.setY(((rgb & 0x0000FF00) >> 8)/256.0);
    color.setZ(((rgb & 0x000000FF) >> 0)/256.0);
}

inline void DrawLine(dmRenderDDF::DrawLine &msg, Vector3 p1,Vector3 p2,uint32 color){;
    msg.m_StartPoint.setX(p1.x);
    msg.m_StartPoint.setY(p1.y);
    msg.m_StartPoint.setZ(p1.z);

    msg.m_EndPoint.setX(p2.x);
    msg.m_EndPoint.setY(p2.y);
    msg.m_EndPoint.setZ(p2.z);

    RGBUintToVector(color,msg.m_Color);
}

static int Draw(lua_State *L){
    DM_LUA_STACK_CHECK(L, 0);
    check_arg_count(L, 1);
    DebugRendererUserdata *userdata = DebugRendererUserdataCheck(L, 1);

    dmGameObject::HInstance instance = dmScript::CheckGOInstance(L);
    dmMessage::URL receiver;
    dmMessage::ResetURL(&receiver);
    dmMessage::Result result = dmMessage::GetSocket(dmRender::RENDER_SOCKET_NAME, &receiver.m_Socket);
    if (result != dmMessage::RESULT_OK){
        luaL_error(L,"The socket '%s' could not be found.", dmRender::RENDER_SOCKET_NAME);
    }

    const Array<DebugRenderer::DebugLine>& lines = userdata->renderer->getLines();
    //dmLogInfo("lines:%d",lines.size());

    dmRenderDDF::DrawLine msg;
    for(int i=0;i<lines.size();i++){
        DebugRenderer::DebugLine line = lines[i];
        DrawLine(msg,line.point1,line.point2,line.color1);
        result = dmMessage::PostDDF(&msg,0x0, &receiver, (uintptr_t) instance,0, 0);
        if(result!=dmMessage::RESULT_OK){luaL_error(L,"can't draw line");}
    }

    const Array<DebugRenderer::DebugTriangle>& triangles = userdata->renderer->getTriangles();
    //dmLogInfo("triangles:%d",triangles.size());
    for(int i=0;i<triangles.size();i++){
        DebugRenderer::DebugTriangle triangle = triangles[i];

        DrawLine(msg,triangle.point1,triangle.point2,triangle.color1);
        result = dmMessage::PostDDF(&msg,0x0, &receiver, (uintptr_t) instance,0, 0);
        if(result!=dmMessage::RESULT_OK){luaL_error(L,"can't draw line");}

        DrawLine(msg,triangle.point2,triangle.point3,triangle.color2);
        result = dmMessage::PostDDF(&msg,0x0, &receiver, (uintptr_t) instance,0, 0);
        if(result!=dmMessage::RESULT_OK){luaL_error(L,"can't draw line");}

        DrawLine(msg,triangle.point3,triangle.point1,triangle.color3);
        result = dmMessage::PostDDF(&msg,0x0, &receiver, (uintptr_t) instance,0, 0);
        if(result!=dmMessage::RESULT_OK){luaL_error(L,"can't draw line");}
    }

	return 0;
}
11 Likes
#3

Very cool!

1 Like