透视投影视锥体

frustum.cpp

@@ -0,0 +1,73 @@
+#include "frustum.h"
+#include "misc.h"
+
+Frustum::Frustum()
+{
+
+}
+
+void Frustum::Init()
+{
+	/*´´½¨program*/
+	mProgram = CreateGPUProgram("res/shader/WhiteColor.vs", "res/shader/WhiteColor.fs");
+
+	mPosLocation = glGetAttribLocation(mProgram, "pos");
+
+	mMLocation = glGetUniformLocation(mProgram, "M");
+	mVLocation = glGetUniformLocation(mProgram, "V");
+	mPLocation = glGetUniformLocation(mProgram, "P");
+}
+
+void Frustum::InitPerspective(float fov, float aspect, float zNear, float zFar)
+{
+	//¼ÆËã½ü¼ô²ÃÃæ
+	float halfFOV = 22.5f;
+	float randianHalfFOV = 3.14*halfFOV / 180.0f;
+	float tanHalfFOV = sinf(randianHalfFOV) / cosf(randianHalfFOV);
+	float yNear = tanHalfFOV * zNear;
+	float xNear = yNear*aspect;
+
+	//¼ÆËãÔ¶¼ô²ÃÃæ
+	float yFar = tanHalfFOV * zFar;
+	float xFar = yFar*aspect;
+
+	float vertexes[24] = {
+		-xNear,-yNear,-zNear,
+		xNear,-yNear,-zNear,
+		xNear,yNear,-zNear,
+		-xNear,yNear,-zNear,
+
+		-xFar,-yFar,-zFar,
+		xFar,-yFar,-zFar,
+		xFar,yFar,-zFar,
+		-xFar,yFar,-zFar,
+	};
+
+	mVBO = CreateBufferObject(GL_ARRAY_BUFFER, sizeof(float)*24, GL_STATIC_DRAW, vertexes);
+
+	unsigned int indexes[] = {
+		0,1,1,2,2,3,3,0, //½ü¼ô²ÃÃæ
+		4,5,5,6,6,7,7,4, //Ô¶¼ô²ÃÃæ
+		0,4,3,7,2,6,1,5
+	};
+	mIBO = CreateBufferObject(GL_ELEMENT_ARRAY_BUFFER, sizeof(int)*24, GL_STATIC_DRAW, indexes);
+
+}
+
+void Frustum::Draw(float* M, float* V, float* P)
+{
+	glUseProgram(mProgram);
+	glUniformMatrix4fv(mMLocation, 1, GL_FALSE, M);
+	glUniformMatrix4fv(mVLocation, 1, GL_FALSE, V);
+	glUniformMatrix4fv(mPLocation, 1, GL_FALSE, P);
+
+	glBindBuffer(GL_ARRAY_BUFFER, mVBO);
+	glEnableVertexAttribArray(mPosLocation);
+	glVertexAttribPointer(mPosLocation, 3, GL_FLOAT, GL_FALSE, sizeof(float) * 3, (void*)0);
+
+	glBindBuffer(GL_ARRAY_BUFFER, 0);
+	glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, mIBO);
+	glDrawElements(GL_LINES, 24, GL_UNSIGNED_INT, 0);
+	glBindBuffer(GL_ELEMENT_ARRAY_BUFFER, 0);
+	glUseProgram(0);
+}

frustum.h

@@ -0,0 +1,14 @@
+#pragma once
+#include "glew.h"
+#include "Glm/glm.hpp"
+#include "Glm/ext.hpp"
+
+class Frustum {
+public:
+	GLuint mVBO, mIBO, mProgram;
+	GLint mPLocation, mVLocation, mMLocation, mPosLocation;
+	Frustum();
+	void Init();
+	void InitPerspective(float fov, float aspect, float zNear, float zFar);
+	void Draw(float* M, float* V, float* P);
+};

main.cpp

@@ -6,6 +6,7 @@
 #include "misc.h"
 #include "model.h"
 #include "timer.h"
+#include "frustum.h"
 #pragma comment(lib,"opengl32.lib")
 #pragma comment(lib, "glew32.lib")
 
@@ -126,7 +127,7 @@ INT WINAPI WinMain(HINSTANCE hinstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine
 
 	/*´´½¨ÎÆÀí*/
 	GLuint mainTexture = CreateTextureFromFile("res/image/stone.jpg");
-	GLuint secondTexture = CreateTextureFromDds("res/image/150001.dds");
+	GLuint secondTexture = CreateTextureFromDds("res/image/camera.dds");
 
 	glClearColor(0.1f, 0.4f, 0.7f, 1.0f);
 	glEnable(GL_DEPTH_TEST);
@@ -142,10 +143,14 @@ INT WINAPI WinMain(HINSTANCE hinstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine
 		0,0,0,1
 	};
 
-	glm::mat4 model = glm::translate(0.0f, 0.0f, -4.0f);
+	glm::mat4 model = glm::translate(-1.0f, 0.0f, -3.0f)*glm::rotate(-20.0f, 0.0f, 1.0f, 0.0f);
 	glm::mat4 projection = glm::perspective(45.0f, (float)windowWidth / (float)windowHeight, 0.1f, 1000.0f);
 	glm::mat4 normalMatrix = glm::inverseTranspose(model);
 
+	Frustum frustum;
+	frustum.Init();
+	frustum.InitPerspective(45.0f, (float)windowWidth / (float)windowHeight, 0.1f, 4.0f);
+
 	/*ÏÔʾ´°¿Ú*/
 	ShowWindow(hwnd, SW_SHOW);
 	UpdateWindow(hwnd);
@@ -162,7 +167,7 @@ INT WINAPI WinMain(HINSTANCE hinstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine
 		glUniformMatrix4fv(PLocation, 1, GL_FALSE, glm::value_ptr(projection));
 		glUniformMatrix4fv(NMLocation, 1, GL_FALSE, glm::value_ptr(normalMatrix));
 
-		glBindTexture(GL_TEXTURE_2D, mainTexture);
+		glBindTexture(GL_TEXTURE_2D, secondTexture);
 		glUniform1i(textureLocation, 0);
 
 		glBindBuffer(GL_ARRAY_BUFFER, vbo);
@@ -190,6 +195,7 @@ INT WINAPI WinMain(HINSTANCE hinstance, HINSTANCE hPrevInstance, LPSTR lpCmdLine
 		}
 
 		glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
+		frustum.Draw(glm::value_ptr(model), identify, glm::value_ptr(projection));
 		what();
 
 		SwapBuffers(dc);

res/shader/WhiteColor.fs

@@ -0,0 +1,3 @@
+void main() {
+	gl_FragColor =vec4(1.0); 
+}

res/shader/WhiteColor.vs

@@ -0,0 +1,9 @@
+attribute vec3 pos;
+
+uniform mat4 M;
+uniform mat4 V;
+uniform mat4 P;
+
+void main() {
+	gl_Position = P*V*M*vec4(pos,1.0);	
+}

shader2.vcxproj

@@ -146,12 +146,14 @@
     </Link>
   </ItemDefinitionGroup>
   <ItemGroup>
+    <ClCompile Include="frustum.cpp" />
     <ClCompile Include="main.cpp" />
     <ClCompile Include="misc.cpp" />
     <ClCompile Include="model.cpp" />
     <ClCompile Include="timer.cpp" />
   </ItemGroup>
   <ItemGroup>
+    <ClInclude Include="frustum.h" />
     <ClInclude Include="misc.h" />
     <ClInclude Include="model.h" />
     <ClInclude Include="timer.h" />
@@ -159,6 +161,8 @@
   <ItemGroup>
     <None Include="res\shader\PointSprite.fs" />
     <None Include="res\shader\PointSprite.vs" />
+    <None Include="res\shader\WhiteColor.fs" />
+    <None Include="res\shader\WhiteColor.vs" />
   </ItemGroup>
   <Import Project="$(VCTargetsPath)\Microsoft.Cpp.targets" />
   <ImportGroup Label="ExtensionTargets">

shader2.vcxproj.filters

@@ -27,6 +27,9 @@
     <ClCompile Include="timer.cpp">
       <Filter>源文件</Filter>
     </ClCompile>
+    <ClCompile Include="frustum.cpp">
+      <Filter>源文件</Filter>
+    </ClCompile>
   </ItemGroup>
   <ItemGroup>
     <ClInclude Include="misc.h">
@@ -38,8 +41,17 @@
     <ClInclude Include="timer.h">
       <Filter>源文件</Filter>
     </ClInclude>
+    <ClInclude Include="frustum.h">
+      <Filter>源文件</Filter>
+    </ClInclude>
   </ItemGroup>
   <ItemGroup>
+    <None Include="res\shader\WhiteColor.fs">
+      <Filter>源文件</Filter>
+    </None>
+    <None Include="res\shader\WhiteColor.vs">
+      <Filter>源文件</Filter>
+    </None>
     <None Include="res\shader\PointSprite.fs">
       <Filter>源文件</Filter>
     </None>