Print

Please login or register.
1 Hour 1 Day 1 Week 1 Month Forever
Login with username, password and session length

Control Flow

2 (2.2%)

Arrays, Strings, Pointers, and References

8 (9%)

Functions

4 (4.5%)

Basic object-oriented programming

30 (33.7%)

A bit more advanced OOP (Composition, Operator overloading, Inheritance, Virtual Functions)

18 (20.2%)

Templates

8 (9%)

Other (Explain)

4 (4.5%)

Working with files?  (Streams)

15 (16.9%)

Total Members Voted: 89

[Farseer]

Man, I suck at this coding stuff.

I can't work out what's wrong with this:-

Spoiler: Function I'm Having Trouble With (click to show/hide)

Code: [Select]

def continuestorymenu(prologuecont,prologueloop):
    prologuecont = continuestory()
    if prologuecont == 1:
        prologueloop = 0
    elif prologuecont == 0:
        sys.exit(0)
    else:
        prologueloop = 1

Spoiler: continuestory Function (click to show/hide)

Code: [Select]

def continuestory():
    return input("Press 1 to continue, press 0 to quit or press any other number to replay.")

Variables, place in code etc:-

Spoiler: Variables (click to show/hide)

Code: [Select]

#Variables to allow loops to finish.
room1loop = 1

endloop = 1

prologueloop1 = 1
prologueloop2 = 1
prologueloop3 = 1

#Miscellanious Variables
horndurability = 100
prologuecont1 = 0
prologuecont2 = 0
prologuecont3 = 0

Spoiler: Place in Code (click to show/hide)

Code: [Select]

while prologueloop1 == 1:
    print "You awake in a dank dungeon."
    print "The little sunlight you have streams through a barred grate at the top of your"
    print "cell."
    print "At least they gave you a decent sized cell."
    print "That doesn't stop your wings from itching, your coat from needing a good brush"
    print "and your horn from needing to be shined."
    print "Oh! You almost forgot for a second there that you were a great and noble"
    print "UNICORNED PEGASUS!"
    print " "
    continuestorymenu(prologuecont1,prologueloop1)
    print " "

The trouble is that it just doesn't work. It doesn't end the loop that I need it to. I tried replacing the prologuecont = continuestory() with prologuecont = input, but that didn't seem to work either.

I'm in Python 2.7.2. Any ideas, guys?

[eerr]

I got 50/50 odds, input returns string-type input

try printing the result of 'input' to check the type.
Casting the result to an integer, then printing the integer.

[Virex]

That's not the problem (well it may be, but there's a more pressing problem). The problem is that in continuestorymenu (have you considered using CamelCase or dashes in your function names yet?) prologuecont is a local variable, so assigning a value to it will not change prologuecont1 and thus the prologue loop will never terminate. To solve this the simplest way would be to just change prologuecont1 directly incontinuestorymenu.
Another option would be to give continuestorymenu a return value that indicates if the loop has to terminate and then bind the prologuecont1 to the return value. That would also get rid of the need to have prologuecont1 as a global variable.

[Farseer]

(have you considered using CamelCase or dashes in your function names yet?)

That might be a good idea. :p

Another option would be to give continuestorymenu a return value that indicates if the loop has to terminate and then bind the prologuecont1 to the return value. That would also get rid of the need to have prologuecont1 as a global variable.

Thanks, I'll try this out. I'll find out how to do it first THEN try it out. :p

[Shades]

(have you considered using CamelCase or dashes in your function names yet?)

I find underscores easier to read myself
But as long as you use something it doesn't matter too much what.

[SolarShado]

(have you considered using CamelCase or dashes in your function names yet?)

I find underscores easier to read myself
But as long as you use something it doesn't matter too much what.

I've always preferred camelCase, using underscores only rarely (looks too much like a space IMO).
Never used dashes, but IIRC they're not allowed in Java (which I learned first), and old habits die hard. Didn't know they were allowed in python...

[Virex]

I don't think they're allowed in Python either. I was thinking of underscores.

[Araph]

I can't believe I haven't looked at this thread before! This is great!

And by that I mean I need help. I'm trying to learn C++ with OpenGL, but it's going really slowly and I'm confused with it. This program is an example from the OpenGL Superbible, but it doesn't work and I'm not sure why.

Spoiler: Block of code (click to show/hide)

Code: [Select]

#include <GLTools.h>
#include <GLShaderManager.h>

#define FREEGLUT_STATIC
#include <GL/glut.h>

GLBatch triangleBatch;
GLBatch squareBatch;
GLShaderManager shaderManager;

GLfloat vVerts[] = { -0.5f, 0.0f, 0.0f, 0.5f, 0.0f, 0.0f, 0.0f, 0.5f, 0.0f };

void ChangeSize(int w,int h)
{
glViewport(0,0,w,h);
}

void SetupRC()
{
glClearColor(0.0f,0.0f,0.0f,1.0f);

shaderManager.InitializeStockShaders();

triangleBatch.Begin(GL_TRIANGLES, 3);
triangleBatch.CopyVertexData3f (vVerts);
triangleBatch.End();
}

void RenderScene(void)
{
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT | GL_STENCIL_BUFFER_BIT);

GLfloat vRed[] = {1.0f, 0.0f, 1.0f};
shaderManager.UseStockShader(GLT_SHADER_IDENTITY, vRed);
triangleBatch.Draw();

glutSwapBuffers();
}

void SpecialKeys(int key, int x, int y)
{
GLfloat stepSize = 0.025;

GLfloat blockX = vVerts[0];
GLfloat blockY = vVerts[7];

if (key == GLUT_KEY_UP)
{ blockY += stepSize;}

vVerts[0]=blockX;
vVerts[1]=blockY;

vVerts[3]=blockX;
vVerts[4]=blockY;

vVerts[6]=blockX;
vVerts[7]=blockY;

vVerts[9]=blockX;
vVerts[10]=blockY;

squareBatch.CopyVertexData3f(vVerts);

glutPostRedisplay();
}

int main(int argc, char* argv[])
{
gltSetWorkingDirectory(argv[0]);

glutInit(&argc, argv);
glutInitDisplayMode(GLUT_DOUBLE | GLUT_RGBA | GLUT_DEPTH | GLUT_STENCIL);
glutInitWindowSize (800, 600);
glutCreateWindow("Triangle");
glutReshapeFunc(ChangeSize);
glutDisplayFunc(RenderScene);

GLenum err = glewInit();
if (GLEW_OK != err)
{
fprintf(stderr, "GLEW Error: %s\n", glewGetErrorString(err));
return 1;
}

SetupRC();

glutSpecialFunc(SpecialKeys);

glutPostRedisplay();

glutMainLoop();

return 0;
}

It's supposed to make a triangle appear on the screen (which it does) and the triangle is supposed to move up when you press the up arrow (but it doesn't). Could anyone point out what I'm doing wrong? It uses FreeGLUT and GLTools.

Also, if this isn't the kind of thread where you post stuff like this, my bad. Sorry.

[olemars]

Code: [Select]

void SpecialKeys(int key, int x, int y)
{
   GLfloat stepSize = 0.025;

   GLfloat blockX = vVerts[0];
   GLfloat blockY = vVerts[7];

   if (key == GLUT_KEY_UP)
   {   blockY += stepSize;}

   vVerts[0]=blockX;
   vVerts[1]=blockY;

   vVerts[3]=blockX;
   vVerts[4]=blockY;

   vVerts[6]=blockX;
   vVerts[7]=blockY;

   vVerts[9]=blockX;
   vVerts[10]=blockY;

   squareBatch.CopyVertexData3f(vVerts);

   glutPostRedisplay();
}
You want to modify the vertex buffer of triangleBatch, not squareBatch (which I assume is just an accidental leftover of prior experiments). Plus you're sort of adding vertices to it (you have nine but are indexing eleven) which will end badly. Only reason this doesn't crash and burn badly is because your renderloop is only drawing the unmodified triangleBatch.

[Araph]

You want to modify the vertex buffer of triangleBatch, not squareBatch (which I assume is just an accidental leftover of prior experiments). Plus you're sort of adding vertices to it (you have nine but are indexing eleven) which will end badly. Only reason this doesn't crash and burn badly is because your renderloop is only drawing the unmodified triangleBatch.

The part about squareBatch is confusing to me; in the book I'm getting the example out of, it says square instead of triangle. Same with the extra vertices. Weird. Maybe I just misread it or something...

Anyway, now the program actually does something! Hooray! Although I'm not sure why the triangle disappears instead of moving, but still.

[Virex]

You could have the vertices defined the wrong way around in the movement code, which would cause the backface culling to kick in.

[olemars]

You want to modify the vertex buffer of triangleBatch, not squareBatch (which I assume is just an accidental leftover of prior experiments). Plus you're sort of adding vertices to it (you have nine but are indexing eleven) which will end badly. Only reason this doesn't crash and burn badly is because your renderloop is only drawing the unmodified triangleBatch.

The part about squareBatch is confusing to me; in the book I'm getting the example out of, it says square instead of triangle. Same with the extra vertices. Weird. Maybe I just misread it or something...

Anyway, now the program actually does something! Hooray! Although I'm not sure why the triangle disappears instead of moving, but still.

The example was probably a square at first, but then they decided on a triangle instead and forgot to edit the whole example.

It disappears because

Code: [Select]

   GLfloat blockX = vVerts[0];
   GLfloat blockY = vVerts[7];

   if (key == GLUT_KEY_UP)
   {   blockY += stepSize;}

   vVerts[0]=blockX;
   vVerts[1]=blockY;

   vVerts[3]=blockX;
   vVerts[4]=blockY;

   vVerts[6]=blockX;
   vVerts[7]=blockY;
here you assign blockX to all x coordinates (vVerts[0], vVerts[3], vVerts[6]), in practice making your first and second vertice have the exact same coordinates and also shifting the third to the left. You really don't have to assign to the X coordinate at all since you're not moving along that axis.

EDIT: Misread it a little. In fact you're assigning the same coordinates to all three vertices, forming a single dot.

[Shades]

EDIT: Misread it a little. In fact you're assigning the same coordinates to all three vertices, forming a single dot.

Good catch, didn't even see that. He probably should just change the 'Y' verts to be += stepSize directly and be done with it, I'm not sure what the setting blockY first is trying to do.

[Siquo]

Also, if this isn't the kind of thread where you post stuff like this, my bad. Sorry.

As you can see, you're in the right place

[Shades]

A potentially useful resource for non/new-coders who want to learn programming: http://learnpythonthehardway.org
Obviously this will teach you python but apparently it's a good grounding in how people learn to program, I've not read it but enough people I know have recommended it that I thought I'd pass on the link.