From ca759c0c82cce0f8c5aad0370df0c162cdab227b Mon Sep 17 00:00:00 2001
From: tatsy <tatsy.mail@gmail.com>
Date: Wed, 23 Mar 2016 17:51:20 +0900
Subject: [PATCH] Image texture mapping class is added.

---
 sources/core/forward_decl.h    |  1 +
 sources/texture/CMakeLists.txt |  2 ++
 sources/texture/imagemap.cc    | 23 ++++++++++++++++++++++
 sources/texture/imagemap.h     | 35 ++++++++++++++++++++++++++++++++++
 4 files changed, 61 insertions(+)
 create mode 100644 sources/texture/imagemap.cc
 create mode 100644 sources/texture/imagemap.h

diff --git a/sources/core/forward_decl.h b/sources/core/forward_decl.h
index c67b033..3ecc0de 100644
--- a/sources/core/forward_decl.h
+++ b/sources/core/forward_decl.h
@@ -40,6 +40,7 @@ namespace spica {
     class Image;
     class Film;
     class MipMap;
+    enum class ImageWrap;
 
     // Math module
     template <class T>
diff --git a/sources/texture/CMakeLists.txt b/sources/texture/CMakeLists.txt
index 8cfd799..493e4e7 100644
--- a/sources/texture/CMakeLists.txt
+++ b/sources/texture/CMakeLists.txt
@@ -1,12 +1,14 @@
 set(SOURCES ${SOURCES}
     ${CMAKE_CURRENT_LIST_DIR}/texture.cc
     ${CMAKE_CURRENT_LIST_DIR}/constant.cc
+    ${CMAKE_CURRENT_LIST_DIR}/imagemap.cc
     ${CMAKE_CURRENT_LIST_DIR}/uv.cc
     PARENT_SCOPE)
 
 set(HEADERS ${HEADERS}
     ${CMAKE_CURRENT_LIST_DIR}/spica_texture.h
     ${CMAKE_CURRENT_LIST_DIR}/constant.h
+    ${CMAKE_CURRENT_LIST_DIR}/imagemap.h
     ${CMAKE_CURRENT_LIST_DIR}/texture.h
     ${CMAKE_CURRENT_LIST_DIR}/uv.h
     PARENT_SCOPE)
diff --git a/sources/texture/imagemap.cc b/sources/texture/imagemap.cc
new file mode 100644
index 0000000..1912eb2
--- /dev/null
+++ b/sources/texture/imagemap.cc
@@ -0,0 +1,23 @@
+#define SPICA_API_EXPORT
+#include "imagemap.h"
+
+#include "../core/point2d.h"
+#include "../math/vector2d.h"
+#include "../image/mipmap.h"
+
+namespace spica {
+
+ImageTexture::ImageTexture(const Image& image,
+                           std::unique_ptr<TextureMapping2D> texmap,
+                           ImageWrap wrap)
+    : mipmap_{ std::make_unique<MipMap>(image, wrap) }
+    , texmap_{ std::move(texmap) } {
+}
+
+Spectrum ImageTexture::evaluate(const SurfaceInteraction& intr) const {
+    Vector2d dstdx, dstdy;
+    Point2d st = texmap_->map(intr);
+    return mipmap_->lookup(st);
+}
+
+}  // namespace spica
diff --git a/sources/texture/imagemap.h b/sources/texture/imagemap.h
new file mode 100644
index 0000000..849706d
--- /dev/null
+++ b/sources/texture/imagemap.h
@@ -0,0 +1,35 @@
+#ifdef _MSC_VER
+#pragma once
+#endif
+
+#ifndef _SPICA_IMAGEMAP_H_
+#define _SPICA_IMAGEMAP_H_
+
+#include <string>
+#include <memory>
+
+#include "../core/common.h"
+#include "../core/forward_decl.h"
+#include "../core/spectrum.h"
+
+#include "texture.h"
+
+namespace spica {
+
+class ImageTexture : public Texture<Spectrum> {
+public:
+    ImageTexture(const Image& image,
+                 std::unique_ptr<TextureMapping2D> texmap,
+                 ImageWrap wrap);
+
+    Spectrum evaluate(const SurfaceInteraction& intr) const;
+
+private:
+    // Private field
+    std::unique_ptr<MipMap> mipmap_;
+    std::unique_ptr<TextureMapping2D> texmap_;
+};
+
+}  // namespace spica
+
+#endif  // _SPICA_IMAGEMAP_H_