Rewrite VertexFormat to support an arbitary amount of components

[libs/gl.git] / source / vertexformat.cpp

diff --git a/source/vertexformat.cpp b/source/vertexformat.cpp
index bf2d9095d77220333ac205a608375450c8ada8c9..232690ede2f99f2c7d1ebb8411d9ad442c68dffa 100644 (file)
--- a/source/vertexformat.cpp
+++ b/source/vertexformat.cpp
@@ -5,16 +5,100 @@ Copyright © 2007  Mikko Rasa, Mikkosoft Productions
 Distributed under the LGPL
 */
 
+#include <cstring>
+#include <msp/strings/lexicalcast.h>
+#include "except.h"
 #include "vertexformat.h"
 
 namespace Msp {
 namespace GL {
 
-uint get_stride(VertexFormat f)
+VertexFormat::VertexFormat():
+       data(0)
+{ }
+
+VertexFormat::VertexFormat(VertexComponent c):
+       data(new unsigned char[8])
+{
+       data[0]=1;
+       data[1]=c;
+}
+
+VertexFormat::VertexFormat(const VertexFormat &f):
+       data(0)
+{
+       if(f.data)
+       {
+               data=new unsigned char[f.data[0]/8+8];
+               memcpy(data, f.data, f.data[0]+1);
+       }
+}
+
+VertexFormat &VertexFormat::operator=(const VertexFormat &f)
+{
+       delete[] data;
+       if(f.data)
+       {
+               data=new unsigned char[f.data[0]/8+8];
+               memcpy(data, f.data, f.data[0]+1);
+       }
+       else
+               data=0;
+
+       return *this;
+}
+
+VertexFormat::~VertexFormat()
+{
+       delete[] data;
+}
+
+VertexFormat operator,(const VertexFormat &f, VertexComponent c)
+{
+       VertexFormat r=f;
+       if(r.data)
+       {
+               const unsigned char n=++r.data[0];
+               if((n&7)==7)
+               {
+                       unsigned char *newdt=new unsigned char[n+9];
+                       memcpy(newdt, r.data, n);
+                       delete r.data;
+                       r.data=newdt;
+               }
+               r.data[n]=c;
+       }
+       else
+       {
+               r.data=new unsigned char[8];
+               r.data[0]=1;
+               r.data[1]=c;
+       }
+
+       return r;
+}
+
+VertexFormat operator,(const VertexFormat &f, unsigned i)
+{
+       if(!f.data)
+               throw InvalidState("VertexFormat has no components");
+       VertexFormat r=f;
+       unsigned char *c=r.data+r.data[0];
+       if(*c<ATTRIB1)
+               throw InvalidState("Last component is not a generic attribute");
+       // VertexArray uses an unsigned to store flags for enabled arrays
+       if(i<1 || i>28)
+               throw InvalidParameterValue("Generic attribute index out of range");
+       *c+=(i-1)*4;
+
+       return r;
+}
+
+uint get_stride(const VertexFormat &f)
 {
        uint stride=0;
-       for(uint fmt=f; fmt; fmt>>=4)
-               stride+=(fmt&3)+1;
+       for(const unsigned char *i=f.begin(); i!=f.end(); ++i)
+               stride+=(*i&3)+1;
        return stride;
 }
 
@@ -24,11 +108,11 @@ std::istream &operator>>(std::istream &in, VertexFormat &f)
        in>>str;
 
        unsigned start=0;
-       f=NODATA;
 
        while(1)
        {
                unsigned underscore=str.find('_', start);
+               bool fail=false;
                if(!str.compare(start, underscore-start, "VERTEX2"))
                        f=(f,VERTEX2);
                else if(!str.compare(start, underscore-start, "VERTEX3"))
@@ -51,7 +135,32 @@ std::istream &operator>>(std::istream &in, VertexFormat &f)
                        f=(f,COLOR3_FLOAT);
                else if(!str.compare(start, underscore-start, "COLOR4F"))
                        f=(f,COLOR4_FLOAT);
+               else if(underscore>=start+8 && !str.compare(start, 6, "ATTRIB"))
+               {
+                       try
+                       {
+                               char n=str[start+6];
+                               unsigned i=lexical_cast<unsigned>(str.substr(start+7, underscore-start-7));
+                               if(n=='1')
+                                       f=(f,ATTRIB1,i);
+                               else if(n=='2')
+                                       f=(f,ATTRIB2,i);
+                               else if(n=='3')
+                                       f=(f,ATTRIB3,i);
+                               else if(n=='4')
+                                       f=(f,ATTRIB4,i);
+                               else
+                                       fail=true;
+                       }
+                       catch(const LexicalError &)
+                       {
+                               fail=true;
+                       }
+               }
                else
+                       fail=true;
+
+               if(fail)
                {
                        in.setstate(std::ios_base::failbit);
                        break;