void DebugRenderer::DrawSolidCircle (const b2Vec2& center, float32 radius, const b2Vec2& axis, const b2Color& color)
{
#ifndef NO_DEBUG_RENDERER
const float32 k_segments = 16.0f;
const int vertexCount = 16;
const float32 k_increment = 2.0f * b2_pi / k_segments;
float32 theta = 0.0f;
GLfloat glVertices[vertexCount * 2];
for (int i = 0; i < k_segments; ++i) {
const b2Vec2 v = center + radius * b2Vec2(cosf(theta), sinf(theta));
glVertices[i * 2] = v.x;
glVertices[i * 2 + 1] = v.y;
theta += k_increment;
}
setColorPointer(color, 0.5f, vertexCount);
glVertexPointer(2, GL_FLOAT, 0, glVertices);
glDrawArrays(GL_TRIANGLE_FAN, 0, vertexCount);
setColorPointer(color, 1.0f, vertexCount);
glDrawArrays(GL_LINE_LOOP, 0, vertexCount);
GL_checkError();
// Draw the axis line
DrawSegment(center, center + radius * axis, color);
#endif
}
void DebugRenderer::DrawSolidPolygon (const b2Vec2* vertices, int vertexCount, const b2Color& color)
{
#ifndef NO_DEBUG_RENDERER
glVertexPointer(2, GL_FLOAT, 0, vertices);
setColorPointer(color, 0.5f, vertexCount);
glDrawArrays(GL_TRIANGLE_FAN, 0, vertexCount);
setColorPointer(color, 1.0f, vertexCount);
glDrawArrays(GL_LINE_LOOP, 0, vertexCount);
GL_checkError();
#endif
}
void DebugRenderer::DrawSegmentWithAlpha (const b2Vec2& p1, const b2Vec2& p2, const b2Color& color, float alpha)
{
#ifndef NO_DEBUG_RENDERER
setColorPointer(color, alpha, 2);
const GLfloat glVertices[] = { p1.x, p1.y, p2.x, p2.y };
glVertexPointer(2, GL_FLOAT, 0, glVertices);
glDrawArrays(GL_LINES, 0, 2);
GL_checkError();
#endif
}
void DebugRenderer::DrawPoint (const b2Vec2& p, float32 size, const b2Color& color)
{
#ifndef NO_DEBUG_RENDERER
setColorPointer(color, 1.0f, 4);
const float minx = p.x - size / 2.0f;
const float maxx = p.x + size / 2.0f;
const float miny = p.y - size / 2.0f;
const float maxy = p.y + size / 2.0f;
const float vertices[] = { minx, miny, maxx, miny, minx, maxy, maxx, maxy };
glVertexPointer(2, GL_FLOAT, 0, vertices);
glDrawArrays(GL_TRIANGLE_STRIP, 0, 4);
GL_checkError();
#endif
}
GLuint Color3DShader::createVertexArrayObject(GLuint vboId, GLsizei stride, const GLvoid* positionOffset, const GLvoid* colorOffset) {
GLuint vaoId;
glGenVertexArrays(1, &vaoId);
glBindVertexArray(vaoId);
glBindBuffer(GL_ARRAY_BUFFER, vboId);
enablePositionPointer();
setPositionPointer(stride, positionOffset);
enableColorPointer();
setColorPointer(stride, colorOffset);
glBindVertexArray(0);
return vaoId;
}