Messages

16

General Jo Engine Help / Re: Help With SGL: Back-Face Culling and Camera Clipping

« on: January 15, 2019, 03:56:46 am »

My clipping issue was solved by

Code: [Select]

slZdsplevel(7);

, thanks guys.

It has, however, introduced a new issue. The camera seems to warp objects near the edge of the screen. I'm not sure if this is a fundamental issue with projections, a feature, or a setting I'm not changing. Images attached. I don't want to go full on orthographic, but the warping seems a bit extreme.

I have also made an attempt to use the Jo Map Editor to import a 3D file I made in Blender and exported as a Collada file, a simple textured cube. I'm fairly certain I created and exported the file correctly, but attempts at loading and drawing the converted 3d model + texture have left nothing on screen. I also discovered that the coordinate points that are apparently generated for my model are massive compared to the numbers I'm used to using. I tried moving backwards by more than the 3276800 units but still saw nothing and polygon counts confirm it. The generated header from the Map Editor .dae conversion is partially below:

Code: [Select]

static POINT    PointCube[] =
{
	{3276800, 3276800, -3276800},
	{3276800, -3276800, -3276800},
	{-3276800, -3276799, -3276800},
	{-3276799, 3276800, -3276800},
	{3276800, 3276798, 3276800},
	{3276798, -3276803, 3276800},
	{-3276800, -3276799, 3276800},
	{-3276800, 3276800, 3276800},
};

static POLYGON    PolygonCube[] =
{
	{{0, 0, -65536}, {0, 1, 2, 3}},
	{{0, -65536, 0}, {4, 7, 6, 5}},
	{{-65536, 0, 0}, {0, 4, 5, 1}},
	{{0, 0, 65536}, {1, 5, 6, 2}},
	{{0, 65536, 65536}, {2, 6, 7, 3}},
	{{65536, 65536, 0}, {4, 0, 3, 7}},
};

17

Share your code / Re: JoMapEditor is now available on GitHub !

« on: January 14, 2019, 10:07:50 pm »

Beginner question: We build this in Visual Studio to run it, right?

18

General Jo Engine Help / Help With SGL: Back-Face Culling and Camera Clipping

« on: January 13, 2019, 04:55:12 am »

I've been struggling with implementing a couple things that relate to SGL. All of my attempts to play with said things have not gone well. Any help would be appreciated.

Back-Face Culling
First, I've had a short conversation on my Youtube channel with XL2 about back-face culling. If I understand correctly, I have to implement this on a quad by quad basis. My confusion is to how, since the documentation doesn't paint much of a picture on how to play with SGL. I am loading an object like so:

Code: [Select]

jo_vertice    metal_crate_1_v[] = JO_3D_CUBE_VERTICES(32);
jo_3d_quad    metal_crate_1_q[6];
int		      metal_crate_1_nq;

//	Load Texture
jo_sprite_add_tga(JO_ROOT_DIR, "BOX.TGA", JO_COLOR_Transparent);
		
//  Write textures
jo_3d_create_cube(metal_crate_1_q, metal_crate_1_v);
metal_crate_1_nq = 6;
for (int i = 0; i < metal_crate_1_nq; ++i)
{
    jo_3d_set_texture(&metal_crate_1_q[i], 0);
}

Drawing it:

Code: [Select]

//  Perform matrix manipulations and draw
jo_3d_push_matrix();
{
    jo_3d_translate_matrix(x, y, z);
    jo_3d_rotate_matrix(rx, ry, rz);
    jo_3d_draw_array(quads, num_quad);
}

//  Restore default matrix
jo_3d_pop_matrix()

If I understand correctly, the flag is an attribute under pdata. Should I be writing this line while writing textures for every quad I want culled? (excuse the bad C, I don't quite know what I'm doing):

Code: [Select]

quad->data->attbl->flag = 0;

Camera Clipping
Second, I've just encountered some trouble while implementing collision. It appears that quads just in front of the camera's position do not get rendered. Is there a way to change the camera's drawing plane (i.e. move the projection surface closer to the camera's position?) I believe this is controlled by a property called ScreenDist in SGL, but I am unsure where to implement said change.

19

Project announcement / Seniriu

« on: January 04, 2019, 10:48:41 pm »

I'm working on a first person role playing game titled Seniriu. The plan is to create a more simplified version of a Daggerfall-like game in a science fiction setting. Right now I am still grappling with how to implement basic in the engine like menus, multiple level locations, game objects, etc.

I am working in JO Engine and do development live on Twitch, using Mednafen as an emulator and test bed until I get a Saturn Satiator for live tests. I plan on pushing these live streams to Youtube and possibly doing a few shorter tutorial videos for JO Engine if there is a demand for it.

You can follow along with my progress on my Twitch page. I will update later with a github for the project code. My Youtube channel hosts older streams and Twitter announces stream announcements.

Twitch Stream: https://www.twitch.tv/emeraldnovagames

Twitter: http://twitter.com/emeraldnovagame

Youtube: https://www.youtube.com/channel/UCLwdwj0wK4RotV0Dmh0DXlQ