StackOverflow2013

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POOpenGL ES EXC_BAD_ACCESS on glDrawArrays
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copied!<p>I'm having an issue rendering in OpenGL ES 1.1 for an iPhone game that I'm building.</p> <p>In short, I am rendering 3 items:</p> <ol> <li>Background (works fine)</li> <li>A number of spherical objects (works fine)</li> <li>A simple line circle that changes size (I am getting a problem here).</li> </ol> <p>Basically, I am getting an EXC_BAD_ACCESS error when I call drawArrays on the circle. I have tested the code in the basic iPhone OpenGL template and it works just fine, so I can't really track why it's not working here. Can someone point me in the right way?</p> <p>Here is the drawCircle code used to render the circle.</p> <pre><code>- (void) drawCircles { if (!m_circleEffects.empty()) { int segments = 24; for (int i = 0; i < m_circleEffects.size(); i++) { glMatrixMode(GL_MODELVIEW); glLoadIdentity(); glTranslatef(m_circleEffects[i].position.x, m_circleEffects[i].position.y, 0); float radius; if(m_circleEffects[i].isPulseOutward) radius = cos(m_circleEffects[i].frameCounter * M_PI / 720); else radius = sin(m_circleEffects[i].frameCounter * M_PI / 720); GLfloat circlePoints[segments * 3]; int count = 0; for (GLfloat i = 0; i < 360.0f; i += (360.0f / segments)) { circlePoints[count++] = (cos(i * M_PI / 180) * radius); circlePoints[count++] = (sin(i * M_PI / 180) * radius); circlePoints[count++] = z + 1; } glEnableClientState(GL_VERTEX_ARRAY); glVertexPointer(3, GL_FLOAT, 0, circlePoints); glDrawArrays(GL_LINE_LOOP, 0, segments); glDisableClientState(GL_VERTEX_ARRAY); } m_circleEffects.clear(); } } </code></pre> <p>And the following is my other rendering code. It is called prior to the above code in the run loop. Everything in the following seems to work OK.</p> <pre><code>- (void)passInVisualsToUse:(vector<Visual>)visuals { frameCounter += 0.2; if (frameCounter >= 360) frameCounter -= 360; glClearColor(0.5f, 0.5f, 0.5f, 1.0f); glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT); glEnableClientState(GL_VERTEX_ARRAY); glEnableClientState(GL_NORMAL_ARRAY); glEnableClientState(GL_TEXTURE_COORD_ARRAY); glEnable(GL_DEPTH_TEST); glEnable(GL_TEXTURE_2D); glDepthMask(GL_FALSE); glBindTexture(GL_TEXTURE_2D, m_backgroundTexture); glDrawTexfOES(0, 0, 0, 480, 320); glDepthMask(GL_TRUE); vector<Visual>::const_iterator visual = visuals.begin(); for (int visualIndex = 0; visual != visuals.end(); ++visual, ++visualIndex) { if (visual->ObjectType == 1) glBindTexture(GL_TEXTURE_2D, m_oneTexture); else if (visual->ObjectType == 2) glBindTexture(GL_TEXTURE_2D, m_twoTexture); else if (visual->ObjectType == 3) glBindTexture(GL_TEXTURE_2D, m_threeTexture); else glBindTexture(GL_TEXTURE_2D, m_fourTexture); // Set the viewport transform. vec3 position = visual->Position; // Set the light position. glMatrixMode(GL_MODELVIEW); glLoadIdentity(); glTranslatef(position.x, position.y, position.z); float rotationAngle = visual->RotationAngle; glRotatef(rotationAngle, 0, 1, 0); float scale = visual->Scale; if (visual->ShouldThrob) { float scaleFactor = scale + sin(frameCounter) / 25; glScalef(scaleFactor, scaleFactor, scale); BOOL isPulseOutward; if (visual->isPulseOutward) isPulseOutward = YES; else isPulseOutward = NO; CircleEffect toAdd; toAdd.position = position; toAdd.frameCounter = frameCounter; toAdd.isPulseOutward = isPulseOutward; m_circleEffects.push_back(toAdd); } else glScalef(scale, scale, scale); // Set the projection transform. float h = (float)screenSize.size.height / (float)screenSize.size.width; mat4 projection = mat4::Ortho(xleft, xright, h * xleft, h * xright, znear, zfar); glMatrixMode(GL_PROJECTION); glLoadMatrixf(projection.Pointer()); // Draw the surface. int stride = sizeof(vec3) + sizeof(vec3) + sizeof(vec2); const GLvoid* texCoordOffset = (const GLvoid*) (2 * sizeof(vec3)); const Drawable& drawable = m_drawables[visualIndex]; glBindBuffer(GL_ARRAY_BUFFER, drawable.VertexBuffer); glVertexPointer(3, GL_FLOAT, stride, 0); const GLvoid* normalOffset = (const GLvoid*) sizeof(vec3); glNormalPointer(GL_FLOAT, stride, normalOffset); glTexCoordPointer(2, GL_FLOAT, stride, texCoordOffset); glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, drawable.IndexBuffer); glDrawElements(GL_TRIANGLES, drawable.IndexCount, GL_UNSIGNED_SHORT, 0); } glDisableClientState(GL_VERTEX_ARRAY); glDisableClientState(GL_NORMAL_ARRAY); glDisableClientState(GL_TEXTURE_COORD_ARRAY); glDisable(GL_DEPTH_TEST); glDisable(GL_TEXTURE_2D); } </code></pre> <p>The relevant buffers have been set-up elsewhere, and as mentioned, the second code all works fine.</p> <p>Basically, I am getting an EXC_BAD_ACCESS on the drawArrays code in the top code snippet. Anyone have any ideas why?</p> <p>Thanks</p>

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