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Ich versuche, ein rotes Rechteck mit zwei Dreiecken zu zeichnen. Ich kann den Bildschirm löschen, aber ich kann meine Dreiecke nicht zum Rendern bringen. Was mache ich falsch?OpenGL ES2 kann nicht angezeigt werden, um etwas anzuzeigen
Solid.vert Shader:
#ifndef STRINGIFY
#define STRINGIFY(a) #a
#endif
char *vsSolid = STRINGIFY(
uniform mat4 Projection;
uniform mat4 ModelView;
attribute vec4 vPosition;
void main()
{
gl_Position = Projection * ModelView * vPosition;
}
);
Solid.frag Shader:
#ifndef STRINGIFY
#define STRINGIFY(a) #a
#endif
char *fsSolid = STRINGIFY(
precision mediump float;
void main()
{
gl_FragColor = vec4(1.0, 0, 0, 1);
}
);
Programm:
#import <Foundation/Foundation.h>
#include "SDL.h"
#include <time.h>
#include "SDL_opengles.h"
#include "SDL_opengles2.h"
#define FALSE 0
#define TRUE 1
#ifndef BOOL
#define BOOL int
#endif
#define min(a,b) ((a) < (b) ? (a) : (b))
#define max(a,b) ((a) > (b) ? (a) : (b))
#define SCREEN_WIDTH 320
#define SCREEN_HEIGHT 480
#include "Solid.vert"
#include "Solid.frag"
GLuint g_SolidProgram = 0;
BOOL g_Running = TRUE;
SDL_Window *g_SDLWindow = NULL;
SDL_Surface *g_SDLSurface = NULL;
SDL_Renderer *g_SDLRenderer = NULL;
SDL_Texture *g_SDLTexture = NULL;
int g_ScreenHeight = SCREEN_HEIGHT;
int g_ScreenWidth = SCREEN_WIDTH;
//--------------------------------------------------------------------------------------------
// BuildShader()
//--------------------------------------------------------------------------------------------
GLuint BuildShader(char *pszSource, GLenum shaderType)
{
GLuint hShader = glCreateShader(shaderType);
glShaderSource(hShader, 1, &pszSource, 0);
glCompileShader(hShader);
GLint compileSuccess;
if(compileSuccess == GL_FALSE)
{
GLchar message[ 256 ];
glGetShaderInfoLog(hShader, sizeof(message), 0, &message[ 0 ]);
printf("%s\n", message);
exit(1);
}
return hShader;
}
//--------------------------------------------------------------------------------------------
// BuildProgram()
//--------------------------------------------------------------------------------------------
GLuint BuildProgram(char *pszVertexShaderSource, char *pszFragmentShaderSource)
{
GLuint vShader = BuildShader(pszVertexShaderSource, GL_VERTEX_SHADER);
GLuint fShader = BuildShader(pszFragmentShaderSource, GL_FRAGMENT_SHADER);
GLuint hProgram = glCreateProgram();
glAttachShader(hProgram, vShader);
glAttachShader(hProgram, fShader);
glLinkProgram(hProgram);
GLint linkSuccess;
glGetProgramiv(hProgram, GL_LINK_STATUS, &linkSuccess);
if(linkSuccess == GL_FALSE)
{
GLchar message[ 256 ];
glGetProgramInfoLog(hProgram, sizeof(message), 0, &message[ 0 ]);
printf("%s\n", message);
exit(1);
}
return hProgram;
}
//--------------------------------------------------------------------------------------------
// ApplyOrtho()
//--------------------------------------------------------------------------------------------
void ApplyOrtho(float maxX, float maxY)
{
float a = 1.0f/maxX;
float b = 1.0f/maxY;
float ortho[ 16 ] =
{
a, 0, 0, 0,
0, b, 0, 0,
0, 0, -1, 0,
0, 0, 0, 1
};
GLint uProjection = glGetUniformLocation(g_SolidProgram, "Projection");
glUniformMatrix4fv(uProjection, 1, 0, &ortho[ 0 ]);
}
//--------------------------------------------------------------------------------------------
// ApplyRotation()
//--------------------------------------------------------------------------------------------
void ApplyRotation(float degrees)
{
float radians = degrees * 3.14159f/180.0f;
float s = sinf(radians);
float c = cosf(radians);
float zRotation[ 16 ] =
{
c, s, 0, 0,
-s, c, 0, 0,
0, 0, 1, 0,
0, 0, 0, 1
};
GLint uModelView = glGetUniformLocation(g_SolidProgram, "ModelView");
glUniformMatrix4fv(uModelView, 1, 0, &zRotation[ 0 ]);
}
//--------------------------------------------------------------------------------------------
// InitSDL()
//--------------------------------------------------------------------------------------------
void InitSDL(void)
{
if(SDL_Init(SDL_INIT_VIDEO) < 0)
exit(-1);
atexit(SDL_Quit);
SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1); // *new*
SDL_DisplayMode currentDisplay;
SDL_GetCurrentDisplayMode(0, ¤tDisplay);
g_ScreenWidth = max(currentDisplay.w, currentDisplay.h);
g_ScreenHeight = min(currentDisplay.w, currentDisplay.h);
SDL_DisplayMode displayMode;
SDL_GetDesktopDisplayMode(0, &displayMode);
SDL_GL_SetAttribute(SDL_GL_CONTEXT_PROFILE_MASK, SDL_GL_CONTEXT_PROFILE_ES);
SDL_GL_SetAttribute(SDL_GL_CONTEXT_MAJOR_VERSION, 2);
SDL_GL_SetAttribute(SDL_GL_CONTEXT_MINOR_VERSION, 0);
SDL_GL_SetAttribute(SDL_GL_DOUBLEBUFFER, 1);
SDL_GL_SetAttribute(SDL_GL_DEPTH_SIZE, 24);
g_SDLWindow = SDL_CreateWindow("Test",
SDL_WINDOWPOS_UNDEFINED,
SDL_WINDOWPOS_UNDEFINED,
g_ScreenWidth,
g_ScreenHeight,
/* SDL_WINDOW_FULLSCFREEN | */ SDL_WINDOW_OPENGL);
if(g_SDLWindow == NULL)
exit(-1);
SDL_GL_CreateContext(g_SDLWindow);
glViewport(0, 0, g_ScreenWidth, g_ScreenHeight); // Reset The Current Viewport
glClearColor(0.9f, 0.9f, 0.9f, 1.0f);
g_SolidProgram = BuildProgram(vsSolid, fsSolid);
glUseProgram(g_SolidProgram);
ApplyOrtho(2, 3);
ApplyRotation(0);
}
// We have to create the vertices of our triangle.
float vertices[] =
{
10.0f, 200.0f, 0.0f,
10.0f, 100.0f, 0.0f,
100.0f, 100.0f, 0.0f,
100.0f, 200.0f, 0.0f,
};
short indices[] =
{
0, 1, 2,
0, 2, 3
}; // The order of vertex rendering.
//--------------------------------------------------------------------------------------------
// Draw()
//--------------------------------------------------------------------------------------------
void Draw(int x, int y)
{
glClear(GL_COLOR_BUFFER_BIT | GL_DEPTH_BUFFER_BIT);
GLuint hPosition = glGetAttribLocation(g_SolidProgram, "vPosition");
glEnableVertexAttribArray(hPosition);
// Prepare the triangle coordinate data
glVertexAttribPointer(hPosition, 3, GL_FLOAT, FALSE, 0, vertices);
// Draw the triangle
glDrawElements(GL_TRIANGLES, 6, GL_UNSIGNED_SHORT, indices);
// Disable vertex array
glDisableVertexAttribArray(hPosition);
}
//--------------------------------------------------------------------------------------------
// main()
//--------------------------------------------------------------------------------------------
int main(int argc, char* argv[])
{
InitSDL();
SDL_Event event;
while(g_Running)
{
while(SDL_PollEvent(&event))
{
switch(event.type)
{
case SDL_QUIT:
g_Running = false;
break;
}
}
Draw(100, 100);
SDL_GL_SwapWindow(g_SDLWindow);
}
SDL_Quit();
return EXIT_SUCCESS;
}