Initial commit of libAgl2 using Pixelflinger2 in external/mesa3d

Somewhat functional, refer to README for details.
Need to enable Android.mk to build.
It builds libGLES_android.so, which needs to replace
 the one in system/lib/egl built by libagl.

Change-Id: Iec3aaa8f3963a4185d81955cd24019eb0c4a5850
Signed-off-by: David Li <davidxli@google.com>
diff --git a/opengl/libagl2/src/vertex.cpp b/opengl/libagl2/src/vertex.cpp
new file mode 100644
index 0000000..021b82b
--- /dev/null
+++ b/opengl/libagl2/src/vertex.cpp
@@ -0,0 +1,373 @@
+#include "gles2context.h"
+
+//#undef LOGD
+//#define LOGD(...)
+
+void GLES2Context::InitializeVertices()
+{
+   vert.vbos = std::map<GLuint, VBO *>(); // the entire struct has been zeroed in constructor
+   vert.free = 1;
+   vert.vbo = NULL;
+   vert.indices = NULL;
+   for (unsigned i = 0; i < GGL_MAXVERTEXATTRIBS; i++)
+      vert.defaultAttribs[i] = Vector4(0,0,0,1);
+}
+
+void GLES2Context::UninitializeVertices()
+{
+   for (std::map<GLuint, VBO *>::iterator it = vert.vbos.begin(); it != vert.vbos.end(); it++) {
+      if (!it->second)
+         continue;
+      free(it->second->data);
+      free(it->second);
+   }
+}
+
+static inline void FetchElement(const GLES2Context * ctx, const unsigned index,
+                                const unsigned maxAttrib, VertexInput * elem)
+{
+   for (unsigned i = 0; i < maxAttrib; i++) {
+      {
+         unsigned size = 0;
+         if (ctx->vert.attribs[i].enabled) {
+            const char * ptr = (const char *)ctx->vert.attribs[i].ptr;
+            ptr += ctx->vert.attribs[i].stride * index;
+            memcpy(elem->attributes + i, ptr, ctx->vert.attribs[i].size * sizeof(float));
+            size = ctx->vert.attribs[i].size;
+//            LOGD("agl2: FetchElement %d attribs size=%d %.2f,%.2f,%.2f,%.2f", i, size, elem->attributes[i].x,
+//                 elem->attributes[i].y, elem->attributes[i].z, elem->attributes[i].w);
+         } else {
+//            LOGD("agl2: FetchElement %d default %.2f,%.2f,%.2f,%.2f", i, ctx->vert.defaultAttribs[i].x,
+//                 ctx->vert.defaultAttribs[i].y, ctx->vert.defaultAttribs[i].z, ctx->vert.defaultAttribs[i].w);
+         }
+
+         switch (size) {
+         case 0: // fall through
+            elem->attributes[i].x = ctx->vert.defaultAttribs[i].x;
+         case 1: // fall through
+            elem->attributes[i].y = ctx->vert.defaultAttribs[i].y;
+         case 2: // fall through
+            elem->attributes[i].z = ctx->vert.defaultAttribs[i].z;
+         case 3: // fall through
+            elem->attributes[i].w = ctx->vert.defaultAttribs[i].w;
+         case 4:
+            break;
+         default:
+            assert(0);
+            break;
+         }
+//         LOGD("agl2: FetchElement %d size=%d %.2f,%.2f,%.2f,%.2f", i, size, elem->attributes[i].x,
+//              elem->attributes[i].y, elem->attributes[i].z, elem->attributes[i].w);
+      }
+   }
+}
+
+template<typename IndexT> static void DrawElementsTriangles(const GLES2Context * ctx,
+      const unsigned count, const IndexT * indices, const unsigned maxAttrib)
+{
+   VertexInput v[3];
+   if (ctx->vert.indices)
+      indices = (IndexT *)((char *)ctx->vert.indices->data + (long)indices);
+   for (unsigned i = 0; i < count; i += 3) {
+      for (unsigned j = 0; j < 3; j++)
+         FetchElement(ctx, indices[i + j], maxAttrib, v + j);
+      ctx->iface->DrawTriangle(ctx->iface, v, v + 1, v + 2);
+   }
+}
+
+static void DrawArraysTriangles(const GLES2Context * ctx, const unsigned first,
+                                const unsigned count, const unsigned maxAttrib)
+{
+//   LOGD("agl: DrawArraysTriangles=%p", DrawArraysTriangles);
+   VertexInput v[3];
+   for (unsigned i = 2; i < count; i+=3) {
+      // TODO: fix order
+      FetchElement(ctx, first + i - 2, maxAttrib, v + 0);
+      FetchElement(ctx, first + i - 1, maxAttrib, v + 1);
+      FetchElement(ctx, first + i - 0, maxAttrib, v + 2);
+      ctx->iface->DrawTriangle(ctx->iface, v + 0, v + 1, v + 2);
+   }
+//   LOGD("agl: DrawArraysTriangles end");
+}
+
+template<typename IndexT> static void DrawElementsTriangleStrip(const GLES2Context * ctx,
+      const unsigned count, const IndexT * indices, const unsigned maxAttrib)
+{
+   VertexInput v[3];
+   if (ctx->vert.indices)
+      indices = (IndexT *)((char *)ctx->vert.indices->data + (long)indices);
+      
+//   LOGD("agl2: DrawElementsTriangleStrip");
+//   for (unsigned i = 0; i < count; i++)
+//      LOGD("indices[%d] = %d", i, indices[i]);
+
+   FetchElement(ctx, indices[0], maxAttrib, v + 0);
+   FetchElement(ctx, indices[1], maxAttrib, v + 1);
+   for (unsigned i = 2; i < count; i ++) {
+      FetchElement(ctx, indices[i], maxAttrib, v + i % 3);
+      ctx->iface->DrawTriangle(ctx->iface, v + (i - 2) % 3, v + (i - 1) % 3 , v + (i + 0) % 3);
+   }
+
+//   for (unsigned i = 2; i < count; i++) {
+//      FetchElement(ctx, indices[i - 2], maxAttrib, v + 0);
+//      FetchElement(ctx, indices[i - 1], maxAttrib, v + 1);
+//      FetchElement(ctx, indices[i - 0], maxAttrib, v + 2);
+//      ctx->iface->DrawTriangle(ctx->iface, v + 0, v + 1, v + 2);
+//   }
+}
+
+static void DrawArraysTriangleStrip(const GLES2Context * ctx, const unsigned first,
+                                    const unsigned count, const unsigned maxAttrib)
+{
+   VertexInput v[3];
+   FetchElement(ctx, first, maxAttrib, v + 0);
+   FetchElement(ctx, first + 1, maxAttrib, v + 1);
+   for (unsigned i = 2; i < count; i++) {
+      // TODO: fix order
+      FetchElement(ctx, first + i, maxAttrib, v + i % 3);
+      ctx->iface->DrawTriangle(ctx->iface, v + (i - 2) % 3, v + (i - 1) % 3 , v + (i + 0) % 3);
+   }
+}
+
+void glBindBuffer(GLenum target, GLuint buffer)
+{
+   GLES2_GET_CONST_CONTEXT(ctx);
+   VBO * vbo = NULL;
+   if (0 != buffer) {
+      std::map<GLuint, VBO *>::iterator it = ctx->vert.vbos.find(buffer);
+      if (it != ctx->vert.vbos.end()) {
+         vbo = it->second;
+         if (!vbo)
+            vbo = (VBO *)calloc(1, sizeof(VBO));
+         it->second = vbo;
+      } else
+         assert(0);
+   }
+   if (GL_ARRAY_BUFFER == target)
+      ctx->vert.vbo = vbo;
+   else if (GL_ELEMENT_ARRAY_BUFFER == target)
+      ctx->vert.indices = vbo;
+   else
+      assert(0);
+   assert(vbo || buffer == 0);
+//   LOGD("\n*\n glBindBuffer 0x%.4X=%d ", target, buffer);
+}
+
+void glBufferData(GLenum target, GLsizeiptr size, const GLvoid* data, GLenum usage)
+{
+   GLES2_GET_CONST_CONTEXT(ctx);
+   if (GL_ARRAY_BUFFER == target) {
+      assert(ctx->vert.vbo);
+      ctx->vert.vbo->data = realloc(ctx->vert.vbo->data, size);
+      ctx->vert.vbo->size = size;
+      ctx->vert.vbo->usage = usage;
+      if (data)
+         memcpy(ctx->vert.vbo->data, data, size);
+   } else if (GL_ELEMENT_ARRAY_BUFFER == target) {
+      assert(ctx->vert.indices);
+      ctx->vert.indices->data = realloc(ctx->vert.indices->data, size);
+      ctx->vert.indices->size = size;
+      ctx->vert.indices->usage = usage;
+      if (data)
+         memcpy(ctx->vert.indices->data, data, size);
+   } else
+      assert(0);
+//   LOGD("\n*\n glBufferData target=0x%.4X size=%u data=%p usage=0x%.4X \n",
+//        target, size, data, usage);
+}
+
+void glBufferSubData(GLenum target, GLintptr offset, GLsizeiptr size, const GLvoid* data)
+{
+   GLES2_GET_CONST_CONTEXT(ctx);
+   if (GL_ARRAY_BUFFER == target)
+   {
+      assert(ctx->vert.vbo);
+      assert(0 <= offset);
+      assert(0 <= size);
+      assert(offset + size <= ctx->vert.vbo->size);
+      memcpy((char *)ctx->vert.vbo->data + offset, data, size);
+   }
+   else
+      assert(0);
+}
+
+void glDeleteBuffers(GLsizei n, const GLuint* buffers)
+{
+   GLES2_GET_CONST_CONTEXT(ctx);
+   for (unsigned i = 0; i < n; i++) {
+      std::map<GLuint, VBO*>::iterator it = ctx->vert.vbos.find(buffers[i]);
+      if (it == ctx->vert.vbos.end())
+         continue;
+      ctx->vert.free = min(ctx->vert.free, buffers[i]);
+      if (it->second == ctx->vert.vbo)
+         ctx->vert.vbo = NULL;
+      else if (it->second == ctx->vert.indices)
+         ctx->vert.indices = NULL;
+      if (it->second) {
+         free(it->second->data);
+         free(it->second);
+      }
+   }
+}
+
+void glDisableVertexAttribArray(GLuint index)
+{
+   GLES2_GET_CONST_CONTEXT(ctx);
+   assert(GGL_MAXVERTEXATTRIBS > index);
+   ctx->vert.attribs[index].enabled = false;
+}
+
+void glDrawArrays(GLenum mode, GLint first, GLsizei count)
+{
+   GLES2_GET_CONST_CONTEXT(ctx);
+//   LOGD("agl2: glDrawArrays=%p", glDrawArrays);
+   assert(ctx->rasterizer.CurrentProgram);
+   assert(0 <= first);
+   int maxAttrib = -1;
+   ctx->iface->ShaderProgramGetiv(ctx->rasterizer.CurrentProgram, GL_ACTIVE_ATTRIBUTES, &maxAttrib);
+   assert(0 <= maxAttrib && GGL_MAXVERTEXATTRIBS >= maxAttrib);
+   switch (mode) {
+   case GL_TRIANGLE_STRIP:
+      DrawArraysTriangleStrip(ctx, first, count, maxAttrib);
+      break;
+   case GL_TRIANGLES:
+      DrawArraysTriangles(ctx, first, count, maxAttrib);
+      break;
+   default:
+      LOGE("agl2: glDrawArrays unsupported mode: 0x%.4X \n", mode);
+      assert(0);
+      break;
+   }
+//   LOGD("agl2: glDrawArrays end");
+}
+
+void glDrawElements(GLenum mode, GLsizei count, GLenum type, const GLvoid* indices)
+{
+   GLES2_GET_CONST_CONTEXT(ctx);
+//   LOGD("agl2: glDrawElements=%p mode=0x%.4X count=%d type=0x%.4X indices=%p",
+//        glDrawElements, mode, count, type, indices);
+   if (!ctx->rasterizer.CurrentProgram)
+      return;
+
+   int maxAttrib = -1;
+   ctx->iface->ShaderProgramGetiv(ctx->rasterizer.CurrentProgram, GL_ACTIVE_ATTRIBUTES, &maxAttrib);
+   assert(0 <= maxAttrib && GGL_MAXVERTEXATTRIBS >= maxAttrib);
+//   LOGD("agl2: glDrawElements mode=0x%.4X type=0x%.4X count=%d program=%p indices=%p \n",
+//        mode, type, count, ctx->rasterizer.CurrentProgram, indices);
+   switch (mode) {
+   case GL_TRIANGLES:
+      if (GL_UNSIGNED_SHORT == type)
+         DrawElementsTriangles<unsigned short>(ctx, count, (unsigned short *)indices, maxAttrib);
+      else
+         assert(0);
+      break;
+   case GL_TRIANGLE_STRIP:
+      if (GL_UNSIGNED_SHORT == type)
+         DrawElementsTriangleStrip<unsigned short>(ctx, count, (unsigned short *)indices, maxAttrib);
+      else
+         assert(0);
+      break;
+   default:
+      assert(0);
+   }
+//   LOGD("agl2: glDrawElements end");
+}
+
+void glEnableVertexAttribArray(GLuint index)
+{
+   GLES2_GET_CONST_CONTEXT(ctx);
+   ctx->vert.attribs[index].enabled = true;
+//   LOGD("agl2: glEnableVertexAttribArray %d \n", index);
+}
+
+void glGenBuffers(GLsizei n, GLuint* buffers)
+{
+   GLES2_GET_CONST_CONTEXT(ctx);
+   for (unsigned i = 0; i < n; i++) {
+      buffers[i] = 0;
+      for (ctx->vert.free; ctx->vert.free < 0xffffffffu; ctx->vert.free++) {
+         if (ctx->vert.vbos.find(ctx->vert.free) == ctx->vert.vbos.end()) {
+            ctx->vert.vbos[ctx->vert.free] = NULL;
+            buffers[i] = ctx->vert.free;
+//            LOGD("glGenBuffers %d \n", buffers[i]);
+            ctx->vert.free++;
+            break;
+         }
+      }
+      assert(buffers[i]);
+   }
+}
+
+void glVertexAttribPointer(GLuint index, GLint size, GLenum type, GLboolean normalized,
+                           GLsizei stride, const GLvoid* ptr)
+{
+   GLES2_GET_CONST_CONTEXT(ctx);
+   assert(GL_FLOAT == type);
+   assert(0 < size && 4 >= size);
+   ctx->vert.attribs[index].size = size;
+   ctx->vert.attribs[index].type = type;
+   ctx->vert.attribs[index].normalized = normalized;
+   if (0 == stride)
+      ctx->vert.attribs[index].stride = size * sizeof(float);
+   else if (stride > 0)
+      ctx->vert.attribs[index].stride = stride;
+   else
+      assert(0);
+//   LOGD("\n*\n*\n* agl2: glVertexAttribPointer program=%u index=%d size=%d stride=%d ptr=%p \n*\n*",
+//        unsigned(ctx->rasterizer.CurrentProgram) ^ 0x04dc18f9, index, size, stride, ptr);
+   if (ctx->vert.vbo)
+      ctx->vert.attribs[index].ptr = (char *)ctx->vert.vbo->data + (long)ptr;
+   else
+      ctx->vert.attribs[index].ptr = ptr;
+//   const float * attrib = (const float *)ctx->vert.attribs[index].ptr;
+//   for (unsigned i = 0; i < 3; i++)
+//      if (3 == size)
+//         LOGD("%.2f %.2f %.2f", attrib[i * 3 + 0], attrib[i * 3 + 1], attrib[i * 3 + 2]);
+//      else if (2 == size)
+//         LOGD("%.2f %.2f", attrib[i * 3 + 0], attrib[i * 3 + 1]);
+   
+}
+
+void glVertexAttrib1f(GLuint indx, GLfloat x)
+{
+   glVertexAttrib4f(indx, x,0,0,1);
+}
+
+void glVertexAttrib1fv(GLuint indx, const GLfloat* values)
+{
+   glVertexAttrib4f(indx, values[0],0,0,1);
+}
+
+void glVertexAttrib2f(GLuint indx, GLfloat x, GLfloat y)
+{
+   glVertexAttrib4f(indx, x,y,0,1);
+}
+
+void glVertexAttrib2fv(GLuint indx, const GLfloat* values)
+{
+   glVertexAttrib4f(indx, values[0],values[1],0,1);
+}
+
+void glVertexAttrib3f(GLuint indx, GLfloat x, GLfloat y, GLfloat z)
+{
+   glVertexAttrib4f(indx, x,y,z,1);
+}
+
+void glVertexAttrib3fv(GLuint indx, const GLfloat* values)
+{
+   glVertexAttrib4f(indx, values[0],values[1],values[2],1);
+}
+
+void glVertexAttrib4f(GLuint indx, GLfloat x, GLfloat y, GLfloat z, GLfloat w)
+{
+   assert(GGL_MAXVERTEXATTRIBS > indx);
+   GLES2_GET_CONST_CONTEXT(ctx);
+//   LOGD("\n*\n*\n agl2: glVertexAttrib4f %d %.2f,%.2f,%.2f,%.2f \n*\n*", indx, x, y, z, w);
+   ctx->vert.defaultAttribs[indx] = Vector4(x,y,z,w);
+   assert(0);
+}
+
+void glVertexAttrib4fv(GLuint indx, const GLfloat* values)
+{
+   glVertexAttrib4f(indx, values[0], values[1], values[2], values[3]);
+}