finished texture unit chapter (and therefore textures section)

src/Engine/Engine.vcxproj

@@ -157,6 +157,7 @@
     <ClInclude Include="mesh\mesh.h" />
     <ClInclude Include="Shaders\Enums.h" />
     <ClInclude Include="Shaders\Shader.h" />
+    <ClInclude Include="textures\Texture2D.h" />
     <ClInclude Include="util\stb_image.h" />
   </ItemGroup>
   <ItemGroup>

src/Engine/Engine.vcxproj.filters

@@ -50,6 +50,9 @@
     <ClInclude Include="util\stb_image.h">
       <Filter>Header Files</Filter>
     </ClInclude>
+    <ClInclude Include="textures\Texture2D.h">
+      <Filter>Header Files</Filter>
+    </ClInclude>
   </ItemGroup>
   <ItemGroup>
     <CopyFileToFolders Include="Shaders\default\default.frag" />

src/Engine/main.cpp

@@ -7,8 +7,8 @@
 #include "shaders/Shader.h"
 #include "util/stb_image.h"
 
-// Continue: https://learnopengl.com/Getting-started/Textures
+// Continue: https://learnopengl.com/Getting-started/Transformations
-// Chapter: Texture Units
+// Chapter: Not started
 //
 
 
@@ -117,6 +117,7 @@ int main()
 	glPolygonMode(GL_FRONT_AND_BACK, GL_FILL);
 	
 	// TEXTURES
+	stbi_set_flip_vertically_on_load(true); // because an image has 0 at top of y axis and opengl expects it to be on the botton, so if this is omitted, the image will be flipped
 	int width, height, nrChannels;
 	unsigned char* image = stbi_load("images/container.jpg", &width, &height, &nrChannels, 0);
 	if (!image)
@@ -125,25 +126,33 @@ int main()
 		stbi_image_free(image);
 		return -1; // it would be better to just use a default error image instead and make the error message a warning message instead
 	}
-	unsigned int textureID;
+	unsigned int textureID_container;
-	glGenTextures(1, &textureID);
+	glGenTextures(1, &textureID_container);
-	glBindTexture(GL_TEXTURE_2D, textureID);
+	glBindTexture(GL_TEXTURE_2D, textureID_container);
 	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height, 0, GL_RGB, GL_UNSIGNED_BYTE, image);
 	glGenerateMipmap(GL_TEXTURE_2D);
 	stbi_image_free(image);
 
-	GLfloat texCoords[] = {
+	image = stbi_load("images/awesomeface.png", &width, &height, &nrChannels, 0);
-	0.0f, 0.0f,  // lower-left corner  
+	if (!image)
-	1.0f, 0.0f,  // lower-right corner
+	{
-	0.5f, 1.0f   // top-center corner
+		std::cerr << "ERROR::IO::LOAD_TEXTURE";
-	};
+		stbi_image_free(image);
+		return -1; // it would be better to just use a default error image instead and make the error message a warning message instead
+	}
+	unsigned int textureID_face;
+	glGenTextures(1, &textureID_face);
+	glBindTexture(GL_TEXTURE_2D, textureID_face);
+	glTexImage2D(GL_TEXTURE_2D, 0, GL_RGB, width, height, 0, GL_RGBA, GL_UNSIGNED_BYTE, image);
+	glGenerateMipmap(GL_TEXTURE_2D);
+	stbi_image_free(image);
+
 	//glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_S, GL_MIRRORED_REPEAT);
 	//glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_WRAP_T, GL_REPEAT);
 	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MIN_FILTER, GL_NEAREST); // use nearest neighbour when zooming out
 	glTexParameteri(GL_TEXTURE_2D, GL_TEXTURE_MAG_FILTER, GL_LINEAR); // use bilinear when zooming in
 
 
-
 	// main loop
 	while(!glfwWindowShouldClose(window))
 	{
@@ -153,11 +162,17 @@ int main()
 		ProcessInput(window);
 
 		shader->Use();
+		shader->setInt("ourTexture1", 0);
+		shader->setInt("ourTexture2", 1);
 		//float time = glfwGetTime();
 		//float greenValue = (sin(time) / 2.0f) + 0.5f;
 		//shader->setFloat("ourColour", 0.0f, greenValue, 0.0f, 0.0f);
 
-		glBindTexture(GL_TEXTURE_2D, textureID);
+		glActiveTexture(GL_TEXTURE0); // before binding texture, activate correct textre Unit (some drivers might show nothing if this is omitted)
+		glBindTexture(GL_TEXTURE_2D, textureID_container);
+		glActiveTexture(GL_TEXTURE0 + 1); // GL_TEXTURE0 + 1 == GL_TEXTURE1, this means looping over multiple units is easily possible
+		glBindTexture(GL_TEXTURE_2D, textureID_face);
+		
 		glBindVertexArray(vertexArrayObject);
 		glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_INT, 0);
 

src/Engine/shaders/default/default.frag

@@ -4,9 +4,10 @@ out vec4 FragColor;
 in vec3 ourColour;
 in vec2 texCoord;
 
-uniform sampler2D ourTexture;
+uniform sampler2D ourTexture1;
+uniform sampler2D ourTexture2;
 
 void main()
 {
-	FragColor = texture(ourTexture, texCoord) * vec4(ourColour, 1.0);
+	FragColor = mix(texture(ourTexture1, texCoord), texture(ourTexture2, texCoord), 0.2) * vec4(ourColour, 1.0);
 }