From d1ba36f4bafef5d6b5e3b63f01fe1d950637df51 Mon Sep 17 00:00:00 2001
From: Bruno Dilly <bdilly@profusion.mobi>
Date: Tue, 3 Jul 2012 23:24:27 +0000
Subject: [PATCH] EPhysics: constraint solver iterations

Functions to get and set the constraint solver number of iterations.

Patch by Leandro Dorileo <dorileo@profusion.mobi>



SVN revision: 73249
---
 legacy/ephysics/src/lib/EPhysics.h         | 36 ++++++++++++++++++++++
 legacy/ephysics/src/lib/ephysics_world.cpp | 24 +++++++++++++++
 2 files changed, 60 insertions(+)

diff --git a/legacy/ephysics/src/lib/EPhysics.h b/legacy/ephysics/src/lib/EPhysics.h
index 5b48fffdef..748dab279c 100644
--- a/legacy/ephysics/src/lib/EPhysics.h
+++ b/legacy/ephysics/src/lib/EPhysics.h
@@ -442,6 +442,42 @@ EAPI Eina_Bool ephysics_world_running_get(const EPhysics_World *world);
  */
 EAPI void ephysics_world_gravity_set(EPhysics_World *world, double gx, double gy);
 
+/**
+ * @brief
+ * Set the number of iterations the constraint solver will have for contact and
+ * joint constraints.
+ *
+ * The default value is set to 10. The greater number of iterations more
+ * quality and precise the result but with performance penalty.
+ *
+ * By default, the Projected Gauss Seidel constraint solver is used for contact
+ * and joint constraints. The algorithm is an iterative LCP solver, informally
+ * known as 'sequential impulse'.
+ *
+ * A reasonable range of iterations is from 4 (low quality, good performance)
+ * to 20 (good quality, less but still reasonable performance).
+ *
+ * @param world The world to be set.
+ * @param iterations The number of iterations to be set.
+ *
+ * @see ephysics_world_constraint_solver_iterations_get().
+ * @ingroup EPhysics_World
+ */
+EAPI void ephysics_world_constraint_solver_iterations_set(EPhysics_World *world, int iterations);
+
+/**
+ * @brief
+ * Get the number of iterations the constraint solver will have for contact and
+ * joint constraints.
+ *
+ * @param world The world to get number of iterations from.
+ * @return the number of iterations set to @p world, or 0 on failure.
+ *
+ * @see ephysics_world_constraint_solver_iterations_set() for its meaning.
+ * @ingroup EPhysics_World
+ */
+EAPI int ephysics_world_constraint_solver_iterations_get(EPhysics_World *world);
+
 /**
  * @brief
  * Get world gravity values for axis x and y.
diff --git a/legacy/ephysics/src/lib/ephysics_world.cpp b/legacy/ephysics/src/lib/ephysics_world.cpp
index ee74844806..235f60e15d 100644
--- a/legacy/ephysics/src/lib/ephysics_world.cpp
+++ b/legacy/ephysics/src/lib/ephysics_world.cpp
@@ -471,6 +471,30 @@ ephysics_world_gravity_set(EPhysics_World *world, double gx, double gy)
    DBG("World %p gravity set to X:%lf, Y:%lf.", world, gx, gy);
 }
 
+EAPI void
+ephysics_world_constraint_solver_iterations_set(EPhysics_World *world, int iterations)
+{
+   if (!world)
+     {
+        ERR("Can't set constraint solver iterations, world is null.");
+        return;
+     }
+
+   world->dynamics_world->getSolverInfo().m_numIterations = iterations;
+}
+
+EAPI int
+ephysics_world_constraint_solver_iterations_get(EPhysics_World *world)
+{
+   if (!world)
+     {
+        ERR("Can't get constraint solver iterations, world is null.");
+        return 0;
+     }
+
+   return world->dynamics_world->getSolverInfo().m_numIterations;
+}
+
 EAPI void
 ephysics_world_gravity_get(const EPhysics_World *world, double *gx, double *gy)
 {