I am not familiar with opengl,can you help me port this to mac?

It crashes on this line: hillVertices[nHillVertices] = (ccVertex2F){pt1.x, pt1.y-(float)textureSize/vSegments*k}; inside Terrain.mm. When the debugger stops me at that line, nHillVertices is some huge number like 1107978021, outside the bounds of the array.

I would have thought that this is related to dividing by 0, but k is initialized to 0 in each iteration, and this crash only happens when I get high in the air and can see alot of hills, so I guess it's not that.

Here's a screenshot of how the game looks when it crashes:

Here's the surrounding code:

nHillVertices = 0;
ccVertex2F p0, p1, pt0, pt1;
p0 = hillKeyPoints[fromKeyPointI];
for (int i=fromKeyPointI+1; i<toKeyPointI+1; i++) {
    p1 = hillKeyPoints[i];

    // triangle strip between p0 and p1
    int hSegments = floorf((p1.x-p0.x)/kHillSegmentWidth);
    int vSegments = 1;
    float dx = (p1.x - p0.x) / hSegments;
    float da = M_PI / hSegments;
    float ymid = (p0.y + p1.y) / 2;
    float ampl = (p0.y - p1.y) / 2;
    pt0 = p0;
    for (int j=1; j<hSegments+1; j++) {
            pt1.x = p0.x + j*dx;
            pt1.y = ymid + ampl * cosf(da*j);
            for (int k=0; k<vSegments+1; k++) {
                hillVertices[nHillVertices] = (ccVertex2F){pt0.x, pt0.y-(float)textureSize/vSegments*k};
                hillTexCoords[nHillVertices++] = (ccVertex2F){pt0.x/(float)textureSize, (float)(k)/vSegments};
                hillVertices[nHillVertices] = (ccVertex2F){pt1.x, pt1.y-(float)textureSize/vSegments*k};
                hillTexCoords[nHillVertices++] = (ccVertex2F){pt1.x/(float)textureSize, (float)(k)/vSegments};
            }
            pt0 = pt1;
        }

        p0 = p1;
    }

Can you make it to cocos2d-x?
´cause I´d like to try it on Android

As otherwise that is not that nice...

I have been reviewing this code for procedural texture generation and seeing how the ground mechanism can be revised. I zoomed out to 0.75 scale and I want to know why the very last triangle appears to be drawn faded as if the highlight method of the render texture does not apply to it. I simply cannot diagnose the root cause and it is driving me absolutely crazy!

It is most noticeable on the very first vertex drawn on the left of the scene and changes over time so presumably is an issue in the resetHillVertices method.

I can only disable the impact of these two triangles by calling glBlend(GL_ONE, GL_ZERO) which makes the hill look really dull.

Setting the vertices used to draw the RenderHighlight to a size significantly larger on the x axis than the texture has no impact on the size of the translucent looking bit.

I have played around with the texture coordinates for the generated vertices with no success as yet can anyone explain this behaviour? I would really like to understand the cause better. I analysed this for a while and it is both the first and last triangles drawn that suffer from this issue.