Image viewer utility

6 files changed, 102 insertions, 3 deletions

diff --git a/src/GFX/Image/PPMParser.cpp b/src/GFX/Image/PPMParser.cpp
index b809ef1..31be0ab 100644
--- a/src/GFX/Image/PPMParser.cpp
+++ b/src/GFX/Image/PPMParser.cpp
@@ -17,7 +17,7 @@ RawImage PPMParser::parse() {
 
     auto pixel_count = header.width * header.height;
 
-    RawImage image(pixel_count, header.width, header.height, 3);
+    RawImage image(header.width, header.height, 3);
     for (uint64_t pixel_index = 0; pixel_index < pixel_count; pixel_index++) {
         RawImage::Pixel pixel = parse_pixel(header.max_color);
         image.add(pixel);
diff --git a/src/GFX/Image/RawImage.hpp b/src/GFX/Image/RawImage.hpp
index 916671b..2b10cb0 100644
--- a/src/GFX/Image/RawImage.hpp
+++ b/src/GFX/Image/RawImage.hpp
@@ -10,9 +10,9 @@ class RawImage {
 public:
     RawImage() : m_pixels(), m_width(0), m_height(0), m_channels(0) {};
 
-    explicit RawImage(size_t pixel_count, uint32_t width, uint32_t height, uint8_t channels)
+    explicit RawImage(uint32_t width, uint32_t height, uint8_t channels)
         : m_pixels(), m_width(width), m_height(height), m_channels(channels) {
-        m_pixels.reserve(pixel_count);
+        m_pixels.reserve(width * height);
     }
 
     struct Pixel {
diff --git a/src/GFX/Shading/Program.cpp b/src/GFX/Shading/Program.cpp
index 2b675f8..6efb30b 100644
--- a/src/GFX/Shading/Program.cpp
+++ b/src/GFX/Shading/Program.cpp
@@ -29,6 +29,10 @@ void Program::bind() const {
     glUseProgram(m_program);
 }
 
+void Program::unbind() const {
+    glUseProgram(0);
+}
+
 Uniform Program::uniform(const std::string& name) const {
     auto index = glGetUniformLocation(m_program, name.c_str());
 
diff --git a/src/GFX/Shading/Program.hpp b/src/GFX/Shading/Program.hpp
index b04dfff..b7db953 100644
--- a/src/GFX/Shading/Program.hpp
+++ b/src/GFX/Shading/Program.hpp
@@ -17,6 +17,7 @@ public:
     Uniform uniform(const std::string& name) const;
 
     void bind() const;
+    void unbind() const;
 
 private:
     uint32_t m_program;
diff --git a/src/Util/ImageViewer.cpp b/src/Util/ImageViewer.cpp
new file mode 100644
index 0000000..76faa3e
--- /dev/null
+++ b/src/Util/ImageViewer.cpp
@@ -0,0 +1,59 @@
+#include <GL/glew.h>
+#include "ImageViewer.hpp"
+
+namespace MC::Util {
+
+void ImageViewer::render() {
+    m_program.bind();
+    m_texture.bind();
+    m_mesh.bind();
+    glDrawElements(GL_TRIANGLES, m_mesh.size(), GL_UNSIGNED_INT, nullptr);
+    m_mesh.unbind();
+    m_texture.unbind();
+    m_program.unbind();
+}
+
+GFX::Mesh ImageViewer::create_default_mesh() {
+    return {{
+        std::vector<Vector<3>>{
+            {0.0f,  1.0f, 0.0f},   // top left
+            {0.0f, 0.0f, 0.0f},   // bottom left
+            {1.0f, 0.0f, 0.0f},   // bottom right
+            {1.0f,  0.0f, 0.0f } // top right
+        },
+        std::vector<Vector<2>>{
+            {1.0f, 1.0f},
+            {1.0f, 0.0f,},
+            {0.0f, 0.0f},
+            {0.0f, 1.0f},
+        },
+    }, {0, 1, 2, 0, 2, 3}};
+}
+
+const char* ImageViewer::vertex = R"v(
+#version 330 core
+
+layout (location = 0) in vec3 position;
+layout (location = 1) in vec2 tex_coord;
+
+out vec2 frag_tex_coord;
+
+void main() {
+    gl_Position = vec4(position, 1.0);
+    frag_tex_coord = tex_coord;
+})v";
+
+const char* ImageViewer::fragment = R"f(
+#version 330 core
+
+uniform sampler2D image;
+
+in vec2 frag_tex_coord;
+out vec4 color;
+
+void main() {
+    //color = texture(image, frag_tex_coord);
+    color = vec4(0.3, 0.5, 1.0, 1.0);
+})f";
+
+}
\ No newline at end of file
diff --git a/src/Util/ImageViewer.hpp b/src/Util/ImageViewer.hpp
new file mode 100644
index 0000000..d583aa8
--- /dev/null
+++ b/src/Util/ImageViewer.hpp
@@ -0,0 +1,35 @@
+#pragma once
+
+#include "../GFX/Image/RawImage.hpp"
+#include "../GFX/Binder.hpp"
+#include "../GFX/Texture.hpp"
+#include "../GFX/Shading/Program.hpp"
+
+namespace MC::Util {
+
+class ImageViewer {
+public:
+    explicit ImageViewer(
+        GFX::Image::RawImage& image
+    ) : m_texture(image),
+        m_program(
+            {GFX::Shading::Shader::Type::Vertex, ImageViewer::vertex},
+            {GFX::Shading::Shader::Type::Fragment, ImageViewer::fragment}
+        ),
+        m_mesh(GFX::Binder::load(default_mesh)) {};
+
+    void render();
+private:
+    static GFX::Mesh create_default_mesh();
+
+    static inline GFX::Mesh default_mesh = create_default_mesh();
+
+    static const char* vertex;
+    static const char* fragment;
+
+    MC::GFX::BindableMesh m_mesh;
+    MC::GFX::Shading::Program m_program;
+    MC::GFX::Texture m_texture;
+};
+
+}
\ No newline at end of file