Hi everyone!

The first milestone in the campaign creation phase is over, so it's time for an update.

The first step in creating a campaign was allowing certain variables to be passed between missions so that the story could modify based on the action taken/decisions made on previous missions. It is now possible to save and request these variables from within a Lua script by calling SaveCampaignVar and GetCampaignVar. The first function takes two arguments, the variable's name and its value, and creates/modifies an entry in the selected team's ini file, in the section corresponding to the campaign. GetCampaignVar takes a single argument, the name of the variable and returns a string value, so it is up to the creator of the script to convert it to whatever type necessary. It is also required that the progress is modified if it is the case.

In order for a new campaign to be added to the game, a directory with the name of the campaign needs to be added in Data/Missions/Campaign. In this directory there has to be a campaign.ini file and scripts for each mission. campaign.ini has to contain the following lines:

MissionNum=number_of_missions
ResetRetry=1 or 0 // whether the progress should be reset in case the player decides to retry a previous level

In addition to these, there needs to be a section for each mission, containing its name and the name of the script (Name and Script).
For example:
[Mission 1]
Name=Ultimate Hedge Mission
Script=ultima.lua

The next step was creating a frame for the story of the campaign. The story in its current state can be found at the links below. Suggestions are welcome!
SPOILER ALERT!
http://dl.dropbox.com/u/69740901/HWStory.odt
http://dl.dropbox.com/u/69740901/HWStory.doc

Hi everyone!

As promised last week, we now have a GL2 version that uses GLSL 1.20 shaders (with a few compatibility propfile features) to render everything.
I've as well replaced all projection related code by using a plain uniform matrix.
This is an essential step towards the non FFP using GLSL 1.30+ transition, which we will need for ES2+ or GL3+ only systems.

So far everything, but the water rendering, runs smooth.
I did not decide, yet, if I shall honor per vertex coloring for all sprites or if we'd have
an additional, independant render pass for the water, as only the water requires this feature.

By next week I hope to have a fully functional GLSL 1.30+ pipeline.
The major changes involved here, are replacing all gl*Pointer stuff with attributes,
as well as removing some leftover FFP state as glColor to uniforms.

Once this is done I'll need to rewrite the stereo rendering, which, due to using quite some FFP, is most likeley broken at the moment.
At that point we should pretty much have forward and backward compatibility ranging from GL1.1 to GL4.x and I can finally start with the actual atlas optimization, which I already prepared two weeks ago.

Hi everyone.

It has been a while since I introduced my project, and I hear that some people are keen to find out what I have been up to so far. Unfortunately, I was very busy during the community bonding period before the official start of the GSoC this week, finishing my university work and moving out of the shared student apartment. This is now all wrapped up though, and I have started working on netplay for Android.

As the first step, I am working on a change that is completely invisible to the player, but will make it easier to implement netplay for iOS and other platforms.

In order to support netplay, the frontend of Hedgewars needs code to communicate with both the server and the game engine, and to pass messages between the two. This code needs to do the same on any platform, but right now the frontend is developed separately for PC, iOS and Android. So, to avoid duplicate work for every frontend, I am working on a portable library that can handle the low-level networking and parsing of messages for all frontends.

So far, I have discussed options for the implementation of this library, tried to find the best networking library that works on all platforms, and decided to use C/C++ combined with SDL_net unless I hit serious problems with it. The big upsides of SDL_net are that it is easy to use, very portable, and we already use it in the game engine, so it does not add a new depencency. On the downside it does not support IPv6, but I hope that this will be added once IPv6 becomes more widely used.

Next, I will look through the existing source code to understand and document the current protocols used between frontend and engine, and between frontend and server.

Hi everyone!
Time for this weeks A&O report.

As indicated by last weeks objectives, I've started reducing the Fixed Function Pipeline (FFP) code,
which became obsolete with GL2 and finally deprecated with GL3/GLES2.

In particular I refactored pretty much all of the matrix related code.
So for me it was just doing some applied linear algebra that week.

OpenGL1 had a so called Matrix stack functioning like this:

glPushMatrix:
Backs up the current matrix.
Most GL implementations don't provide pusing more than 16 times, however Hedgewars required only one time.

glPopMatrix:
Restores the most recently pushed matrix.

glLoadIdentity:
Sets the current matrix to identity (1)

glScale, glTranslate, glRotate, glOrtho2d, (gl utility funcs gluPerspective gluOrtho):
Multiply the current matrix with specific matrices thus chaining the mapping.

These functions allowed for easy chaining of transformations like:
glRotate(), glTranslate(), glScale() would first rotate the object around its center
then move it along the rotated coordinate system and then scale the object.

As already stated this functionality became completley stripped at some point.
So I either had to emulate existing functionality with an own matrix stack and replacement versions of all the above functions, or I could explicitly calculate matrices
as needed.
The later option was quite a nice way to go, as Hedgewars first of all just uses 2d transforms
and futhermore all of them were composed like "translate rotate translate".

Thus replacing the reoccuring pattern of:
glPushMatrix() glTranslate(x, y, 0) glRotate(angle, 0, 0, 1); glTranslate(s, t, 0); glPopMatrix();

with:
m = calculate(x, y, angle, s, t); glLoadMatrix(m);

was a quite straight way to go, as opposed to use full blown matrix multiplications.

To keep the impact of the changeset low I decided to not have some god-function as calculate() above,
but provided utility funcs that semantically m

Weekly A&O report Hi everyone! I'm back with a new weekly A&O, trying you to illustrate what changed since last week. As planned, I refactored the encoding of sprites. But imagages probably tell more than words:

The image to the right shows the old encoding sprites had. TTexture described a sprite/texture as a single, shared entity defined by it's width (s.w) and height (s.h), together with the actual image data of the sprite (the rect portion within the black rect). However due to hardware restrictions the actual texture might need to be of a certain size and thus to be larger.

The new encoding splits TTexture to two independant entities. A sprite now stores information about its size and references to physical image by storing a link to it and a position where the sprite is located.

This encoding allows to pack multiple sprites (red rects) into a shared image (black rect). Doing so may reduce the amount of unused empty space as well as the total count of black rects. Graphics hardware generally benefits from both.

Right now however each sprite (red rect) will be created together with a unique texture (black rect) and stored in the lowever left of it, mimicing exactly the original behaviour. The next step on this frontier obviously will be taking the rectangle packer and allocate multiple sprites within shared textures.

Before doing this step however, I'll continue with removing as much deprecated OpenGL1.x as possible and probably write some GL2 renderer.