Add GX_SetTevIndWarp Function (#66)

* Implement GX_SetTevIndWarp

* Expose GX_SetTevIndWarp

* Document GX_SetTevIndWarp

Author: gamemasterplc

gc/ogc/gx.h

@@ -3418,6 +3418,20 @@ void GX_SetTevIndBumpXYZ(u8 tevstage,u8 indstage,u8 mtx_sel);
  */
 void GX_SetTevIndTile(u8 tevstage,u8 indtexid,u16 tilesize_x,u16 tilesize_y,u16 tilespacing_x,u16 tilespacing_y,u8 indtexfmt,u8 indtexmtx,u8 bias_sel,u8 alpha_sel);
 
+/*!
+ * \fn void GX_SetTevIndWarp(u8 tevstage, u8 indtexid, u8 bias_flag, u8 replace_tex, u8 mtxid)
+ * \brief Used to warp a normal texture lookup using an indirect texture map with 8-bit offsets.
+ *
+ * \param[in] tevstage \ref tevstage that is being affected
+ * \param[in] indtexid \ref indtexstage results to use with this TEV stage
+ * \param[in] bias_flag biases the indirect texture map offsets by -128 if the value is GX_TRUE
+ * \param[in] replace_tex GX_TRUE makes the indirect texture map offsets replace the input texture coordinates rather than offset them as with GX_FALSE
+ * \param[in] mtxid which \ref indtexmtx to use for warping the texture
+ * \return none
+ */
+	   
+void GX_SetTevIndWarp(u8 tevstage, u8 indtexid, u8 bias_flag, u8 replace_tex, u8 mtxid);
+	   
 /*!
  * \fn void GX_SetTevIndRepeat(u8 tevstage)
  * \brief Set a given TEV stage to use the same texture coordinates as were computed in the previous stage.

libogc/gx.c

@@ -4174,6 +4174,21 @@ void GX_SetIndTexCoordScale(u8 indtexid,u8 scale_s,u8 scale_t)
 	}
 }
 
+void GX_SetTevIndWarp(u8 tevstage, u8 indtexid, u8 bias_flag, u8 replace_tex, u8 mtxid)
+{
+	u8 wrap = GX_ITW_OFF;
+	u8 bias = GX_ITB_NONE;
+	if(replace_tex)
+	{
+		wrap = GX_ITW_0;
+	}
+	if(bias_flag)
+	{
+		bias = GX_ITB_STU;
+	}
+	GX_SetTevIndirect(tevstage, indtexid, GX_ITF_8, bias, mtxid, wrap, wrap, GX_FALSE, GX_FALSE, GX_ITBA_OFF);
+}
+
 void GX_SetTevIndTile(u8 tevstage,u8 indtexid,u16 tilesize_x,u16 tilesize_y,u16 tilespacing_x,u16 tilespacing_y,u8 indtexfmt,u8 indtexmtx,u8 bias_sel,u8 alpha_sel)
 {
 	s32 wrap_s,wrap_t;