path: root/tests/glfw/heightmap.c

//========================================================================
// Heightmap example program using OpenGL 3 core profile
// Copyright (c) 2010 Olivier Delannoy
//
// This software is provided 'as-is', without any express or implied
// warranty. In no event will the authors be held liable for any damages
// arising from the use of this software.
//
// Permission is granted to anyone to use this software for any purpose,
// including commercial applications, and to alter it and redistribute it
// freely, subject to the following restrictions:
//
// 1. The origin of this software must not be misrepresented; you must not
//    claim that you wrote the original software. If you use this software
//    in a product, an acknowledgment in the product documentation would
//    be appreciated but is not required.
//
// 2. Altered source versions must be plainly marked as such, and must not
//    be misrepresented as being the original software.
//
// 3. This notice may not be removed or altered from any source
//    distribution.
//
//========================================================================

#include <stdlib.h>
#include <stdio.h>
#include <math.h>
#include <assert.h>
#include <stddef.h>
#include "getopt.h"

#ifdef EMSCRIPTEN
#include <emscripten/emscripten.h>
#endif

#define GLFW_NO_GLU 1 
#include <GL/glfw.h>

/* OpenGL 3.3 support  
 * Functions are effectively mapped in init_opengl() */
#ifndef GL_VERSION_3_0
/* no defines */
#endif

#ifndef GL_VERSION_2_0

typedef char GLchar;

#define GL_BLEND_EQUATION_RGB             0x8009
#define GL_VERTEX_ATTRIB_ARRAY_ENABLED    0x8622
#define GL_VERTEX_ATTRIB_ARRAY_SIZE       0x8623
#define GL_VERTEX_ATTRIB_ARRAY_STRIDE     0x8624
#define GL_VERTEX_ATTRIB_ARRAY_TYPE       0x8625
#define GL_CURRENT_VERTEX_ATTRIB          0x8626
#define GL_VERTEX_PROGRAM_POINT_SIZE      0x8642
#define GL_VERTEX_ATTRIB_ARRAY_POINTER    0x8645
#define GL_STENCIL_BACK_FUNC              0x8800
#define GL_STENCIL_BACK_FAIL              0x8801
#define GL_STENCIL_BACK_PASS_DEPTH_FAIL   0x8802
#define GL_STENCIL_BACK_PASS_DEPTH_PASS   0x8803
#define GL_MAX_DRAW_BUFFERS               0x8824
#define GL_DRAW_BUFFER0                   0x8825
#define GL_DRAW_BUFFER1                   0x8826
#define GL_DRAW_BUFFER2                   0x8827
#define GL_DRAW_BUFFER3                   0x8828
#define GL_DRAW_BUFFER4                   0x8829
#define GL_DRAW_BUFFER5                   0x882A
#define GL_DRAW_BUFFER6                   0x882B
#define GL_DRAW_BUFFER7                   0x882C
#define GL_DRAW_BUFFER8                   0x882D
#define GL_DRAW_BUFFER9                   0x882E
#define GL_DRAW_BUFFER10                  0x882F
#define GL_DRAW_BUFFER11                  0x8830
#define GL_DRAW_BUFFER12                  0x8831
#define GL_DRAW_BUFFER13                  0x8832
#define GL_DRAW_BUFFER14                  0x8833
#define GL_DRAW_BUFFER15                  0x8834
#define GL_BLEND_EQUATION_ALPHA           0x883D
#define GL_MAX_VERTEX_ATTRIBS             0x8869
#define GL_VERTEX_ATTRIB_ARRAY_NORMALIZED 0x886A
#define GL_MAX_TEXTURE_IMAGE_UNITS        0x8872
#define GL_FRAGMENT_SHADER                0x8B30
#define GL_VERTEX_SHADER                  0x8B31
#define GL_MAX_FRAGMENT_UNIFORM_COMPONENTS 0x8B49
#define GL_MAX_VERTEX_UNIFORM_COMPONENTS  0x8B4A
#define GL_MAX_VARYING_FLOATS             0x8B4B
#define GL_MAX_VERTEX_TEXTURE_IMAGE_UNITS 0x8B4C
#define GL_MAX_COMBINED_TEXTURE_IMAGE_UNITS 0x8B4D
#define GL_SHADER_TYPE                    0x8B4F
#define GL_FLOAT_VEC2                     0x8B50
#define GL_FLOAT_VEC3                     0x8B51
#define GL_FLOAT_VEC4                     0x8B52
#define GL_INT_VEC2                       0x8B53
#define GL_INT_VEC3                       0x8B54
#define GL_INT_VEC4                       0x8B55
#define GL_BOOL                           0x8B56
#define GL_BOOL_VEC2                      0x8B57
#define GL_BOOL_VEC3                      0x8B58
#define GL_BOOL_VEC4                      0x8B59
#define GL_FLOAT_MAT2                     0x8B5A
#define GL_FLOAT_MAT3                     0x8B5B
#define GL_FLOAT_MAT4                     0x8B5C
#define GL_SAMPLER_1D                     0x8B5D
#define GL_SAMPLER_2D                     0x8B5E
#define GL_SAMPLER_3D                     0x8B5F
#define GL_SAMPLER_CUBE                   0x8B60
#define GL_SAMPLER_1D_SHADOW              0x8B61
#define GL_SAMPLER_2D_SHADOW              0x8B62
#define GL_DELETE_STATUS                  0x8B80
#define GL_COMPILE_STATUS                 0x8B81
#define GL_LINK_STATUS                    0x8B82
#define GL_VALIDATE_STATUS                0x8B83
#define GL_INFO_LOG_LENGTH                0x8B84
#define GL_ATTACHED_SHADERS               0x8B85
#define GL_ACTIVE_UNIFORMS                0x8B86
#define GL_ACTIVE_UNIFORM_MAX_LENGTH      0x8B87
#define GL_SHADER_SOURCE_LENGTH           0x8B88
#define GL_ACTIVE_ATTRIBUTES              0x8B89
#define GL_ACTIVE_ATTRIBUTE_MAX_LENGTH    0x8B8A
#define GL_FRAGMENT_SHADER_DERIVATIVE_HINT 0x8B8B
#define GL_SHADING_LANGUAGE_VERSION       0x8B8C
#define GL_CURRENT_PROGRAM                0x8B8D
#define GL_POINT_SPRITE_COORD_ORIGIN      0x8CA0
#define GL_LOWER_LEFT                     0x8CA1
#define GL_UPPER_LEFT                     0x8CA2
#define GL_STENCIL_BACK_REF               0x8CA3
#define GL_STENCIL_BACK_VALUE_MASK        0x8CA4
#define GL_STENCIL_BACK_WRITEMASK         0x8CA5
#endif 



#ifndef GL_VERSION_1_5

typedef ptrdiff_t GLintptr;
typedef ptrdiff_t GLsizeiptr;

#define GL_BUFFER_SIZE                    0x8764
#define GL_BUFFER_USAGE                   0x8765
#define GL_QUERY_COUNTER_BITS             0x8864
#define GL_CURRENT_QUERY                  0x8865
#define GL_QUERY_RESULT                   0x8866
#define GL_QUERY_RESULT_AVAILABLE         0x8867
#define GL_ARRAY_BUFFER                   0x8892
#define GL_ELEMENT_ARRAY_BUFFER           0x8893
#define GL_ARRAY_BUFFER_BINDING           0x8894
#define GL_ELEMENT_ARRAY_BUFFER_BINDING   0x8895
#define GL_VERTEX_ATTRIB_ARRAY_BUFFER_BINDING 0x889F
#define GL_READ_ONLY                      0x88B8
#define GL_WRITE_ONLY                     0x88B9
#define GL_READ_WRITE                     0x88BA
#define GL_BUFFER_ACCESS                  0x88BB
#define GL_BUFFER_MAPPED                  0x88BC
#define GL_BUFFER_MAP_POINTER             0x88BD
#define GL_STREAM_DRAW                    0x88E0
#define GL_STREAM_READ                    0x88E1
#define GL_STREAM_COPY                    0x88E2
#define GL_STATIC_DRAW                    0x88E4
#define GL_STATIC_READ                    0x88E5
#define GL_STATIC_COPY                    0x88E6
#define GL_DYNAMIC_DRAW                   0x88E8
#define GL_DYNAMIC_READ                   0x88E9
#define GL_DYNAMIC_COPY                   0x88EA
#define GL_SAMPLES_PASSED                 0x8914
#endif 




/* OpenGL 3.0 */
typedef void (APIENTRY * PFN_glGenVertexArrays)(GLsizei n, GLuint *arrays);
typedef void (APIENTRY * PFN_glBindVertexArray)(GLuint array);
typedef void (APIENTRY * PFN_glDeleteVertexArrays)(GLsizei n, GLuint *arrays);
/* OpenGL 2.0 */
typedef GLuint (APIENTRY * PFN_glCreateShader)(GLenum type);
typedef void (APIENTRY * PFN_glDeleteShader)(GLuint shader);
typedef void (APIENTRY * PFN_glCompileShader)(GLuint shader);
typedef void (APIENTRY * PFN_glShaderSource)(GLuint shader, GLsizei count, const GLchar* *string, const GLint *length);
typedef void (APIENTRY * PFN_glGetShaderiv)(GLuint shader, GLenum pname, GLint *params);
typedef void (APIENTRY * PFN_glGetShaderInfoLog)(GLuint shader, GLsizei bufSize, GLsizei *length, GLchar *infoLog);
typedef GLuint (APIENTRY * PFN_glCreateProgram)(void);
typedef void (APIENTRY * PFN_glDeleteProgram)(GLuint program);
typedef void (APIENTRY * PFN_glAttachShader)(GLuint program, GLuint shader);
typedef void (APIENTRY * PFN_glLinkProgram)(GLuint program);
typedef void (APIENTRY * PFN_glGetProgramiv)(GLuint program, GLenum pname, GLint *params);
typedef void (APIENTRY * PFN_glGetProgramInfoLog)(GLuint shader, GLsizei bufSize, GLsizei *length, GLchar *infoLog);
typedef void (APIENTRY * PFN_glValidateProgram)(GLuint program);
typedef void (APIENTRY * PFN_glUseProgram)(GLuint program);
typedef GLint (APIENTRY * PFN_glGetUniformLocation)(GLuint program, const GLchar *name);
typedef void (APIENTRY * PFN_glUniformMatrix4fv)(GLint location, GLsizei count, GLboolean transpose, const GLfloat *value);
typedef GLint (APIENTRY * PFN_glGetAttribLocation)(GLuint program, const GLchar *name);
typedef void (APIENTRY * PFN_glEnableVertexAttribArray)(GLuint index);
typedef void (APIENTRY * PFN_glVertexAttrib1f)(GLuint index, GLfloat x);
typedef void (APIENTRY * PFN_glVertexAttribPointer)(GLuint index, GLint size, GLenum type, GLboolean normalized, GLsizei stride, const GLvoid *pointer);
/* OpenGL 1.5 */ 
typedef void (APIENTRY * PFN_glBindBuffer)(GLenum target, GLuint buffer);
typedef void (APIENTRY * PFN_glDeleteBuffers)(GLsizei n, const GLuint *buffers);
typedef void (APIENTRY * PFN_glGenBuffers)(GLsizei n, GLuint *buffers);
typedef void (APIENTRY * PFN_glBufferData)(GLenum target, GLsizeiptr size, const GLvoid *data, GLenum usage);