obs-studio/libobs-opengl/gl-helpers.h

/******************************************************************************
    Copyright (C) 2023 by Lain Bailey <[email protected]>

    This program is free software: you can redistribute it and/or modify
    it under the terms of the GNU General Public License as published by
    the Free Software Foundation, either version 2 of the License, or
    (at your option) any later version.

    This program is distributed in the hope that it will be useful,
    but WITHOUT ANY WARRANTY; without even the implied warranty of
    MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
    GNU General Public License for more details.

    You should have received a copy of the GNU General Public License
    along with this program.  If not, see <http://www.gnu.org/licenses/>.
******************************************************************************/

#pragma once

static const char *gl_error_to_str(GLenum errorcode)
{
	static const struct {
		GLenum error;
		const char *str;
	} err_to_str[] = {
		{
			GL_INVALID_ENUM,
			"GL_INVALID_ENUM",
		},
		{
			GL_INVALID_VALUE,
			"GL_INVALID_VALUE",
		},
		{
			GL_INVALID_OPERATION,
			"GL_INVALID_OPERATION",
		},
		{
			GL_INVALID_FRAMEBUFFER_OPERATION,
			"GL_INVALID_FRAMEBUFFER_OPERATION",
		},
		{
			GL_OUT_OF_MEMORY,
			"GL_OUT_OF_MEMORY",
		},
		{
			GL_STACK_UNDERFLOW,
			"GL_STACK_UNDERFLOW",
		},
		{
			GL_STACK_OVERFLOW,
			"GL_STACK_OVERFLOW",
		},
	};
	for (size_t i = 0; i < sizeof(err_to_str) / sizeof(*err_to_str); i++) {
		if (err_to_str[i].error == errorcode)
			return err_to_str[i].str;
	}
	return "Unknown";
}

/*
 * Okay, so GL error handling is..  unclean to work with.  I don't want
 * to have to keep typing out the same stuff over and over again do I'll just
 * make a bunch of helper functions to make it a bit easier to handle errors
 */

static inline bool gl_success(const char *funcname)
{
	GLenum errorcode = glGetError();
	if (errorcode != GL_NO_ERROR) {
		int attempts = 8;
		do {
			blog(LOG_ERROR,
			     "%s failed, glGetError returned %s(0x%X)",
			     funcname, gl_error_to_str(errorcode), errorcode);
			errorcode = glGetError();

			--attempts;
			if (attempts == 0) {
				blog(LOG_ERROR,
				     "Too many GL errors, moving on");
				break;
			}
		} while (errorcode != GL_NO_ERROR);
		return false;
	}

	return true;
}

static inline bool gl_gen_textures(GLsizei num_texture, GLuint *textures)
{
	glGenTextures(num_texture, textures);
	return gl_success("glGenTextures");
}

static inline bool gl_bind_texture(GLenum target, GLuint texture)
{
	glBindTexture(target, texture);
	return gl_success("glBindTexture");
}

static inline void gl_delete_textures(GLsizei num_buffers, GLuint *buffers)
{
	glDeleteTextures(num_buffers, buffers);
	gl_success("glDeleteTextures");
}

static inline bool gl_gen_buffers(GLsizei num_buffers, GLuint *buffers)
{
	glGenBuffers(num_buffers, buffers);
	return gl_success("glGenBuffers");
}

static inline bool gl_bind_buffer(GLenum target, GLuint buffer)
{
	glBindBuffer(target, buffer);
	return gl_success("glBindBuffer");
}

static inline void gl_delete_buffers(GLsizei num_buffers, GLuint *buffers)
{
	glDeleteBuffers(num_buffers, buffers);
	gl_success("glDeleteBuffers");
}

static inline bool gl_gen_vertex_arrays(GLsizei num_arrays, GLuint *arrays)
{
	glGenVertexArrays(num_arrays, arrays);
	return gl_success("glGenVertexArrays");
}

static inline bool gl_bind_vertex_array(GLuint array)
{
	glBindVertexArray(array);
	return gl_success("glBindVertexArray");
}

static inline void gl_delete_vertex_arrays(GLsizei num_arrays, GLuint *arrays)
{
	glDeleteVertexArrays(num_arrays, arrays);
	gl_success("glDeleteVertexArrays");
}

static inline bool gl_bind_renderbuffer(GLenum target, GLuint buffer)
{
	glBindRenderbuffer(target, buffer);
	return gl_success("glBindRendebuffer");
}

static inline bool gl_gen_framebuffers(GLsizei num_arrays, GLuint *arrays)
{
	glGenFramebuffers(num_arrays, arrays);
	return gl_success("glGenFramebuffers");
}

static inline bool gl_bind_framebuffer(GLenum target, GLuint buffer)
{
	glBindFramebuffer(target, buffer);
	return gl_success("glBindFramebuffer");
}

static inline void gl_delete_framebuffers(GLsizei num_arrays, GLuint *arrays)
{
	glDeleteFramebuffers(num_arrays, arrays);
	gl_success("glDeleteFramebuffers");
}

static inline bool gl_tex_param_f(GLenum target, GLenum param, GLfloat val)
{
	glTexParameterf(target, param, val);
	return gl_success("glTexParameterf");
}

static inline bool gl_tex_param_fv(GLenum target, GLenum param, GLfloat *val)
{
	glTexParameterfv(target, param, val);
	return gl_success("glTexParameterf");
}

static inline bool gl_tex_param_i(GLenum target, GLenum param, GLint val)
{
	glTexParameteri(target, param, val);
	return gl_success("glTexParameteri");
}

static inline bool gl_active_texture(GLenum texture_id)
{
	glActiveTexture(texture_id);
	return gl_success("glActiveTexture");
}

static inline bool gl_enable(GLenum capability)
{
	glEnable(capability);
	return gl_success("glEnable");
}

static inline bool gl_disable(GLenum capability)
{
	glDisable(capability);
	return gl_success("glDisable");
}

static inline bool gl_cull_face(GLenum faces)
{
	glCullFace(faces);
	return gl_success("glCullFace");
}

static inline bool gl_get_integer_v(GLenum pname, GLint *params)
{
	glGetIntegerv(pname, params);
	return gl_success("glGetIntegerv");
}

extern bool gl_init_face(GLenum target, GLenum type, uint32_t num_levels,
			 GLenum format, GLint internal_format, bool compressed,
			 uint32_t width, uint32_t height, uint32_t size,
			 const uint8_t ***p_data);

extern bool gl_copy_texture(struct gs_device *device, struct gs_texture *dst,
			    uint32_t dst_x, uint32_t dst_y,
			    struct gs_texture *src, uint32_t src_x,
			    uint32_t src_y, uint32_t width, uint32_t height);

extern bool gl_create_buffer(GLenum target, GLuint *buffer, GLsizeiptr size,
			     const GLvoid *data, GLenum usage);

extern bool update_buffer(GLenum target, GLuint buffer, const void *data,
			  size_t size);