opengl_learn

commit debe4ab718c941c356140b18a5c09c0d819220cf
parent a549948ba1abaf0e31c98287d814e0ae6a6af125
Author: David DiPaola <DavidDiPaola@users.noreply.github.com>
Date:   Wed, 27 Jun 2018 08:22:54 -0400

00: made shader variable naming match 01, 02, 03

Diffstat:
M
00-triangle.c
 | 
13
+++++++------

1 file changed, 7 insertions(+), 6 deletions(-)
diff --git a/00-triangle.c b/00-triangle.c
@@ -19,12 +19,13 @@ int
 main() {
 	GLFWwindow * window = ogl_init(400, 240, "00 - triangle");
 
+	/* vu: vertex shader uniform,  va: vertex shader attribute,  fu: fragment shader uniform,  fv: fragment shader varying */
 	const char * program_vertex_source =
 		"#version 100" "\n"
 		"precision highp float;" "\n"
-		"attribute vec3 attribute_position;" "\n"  /* attributes are inputs to vertex shaders */
+		"attribute vec3 va_vertex_position;" "\n"  /* attributes are inputs to vertex shaders */
 		"void main(){" "\n"
-		"	gl_Position = vec4(attribute_position,1);" "\n"
+		"	gl_Position = vec4(va_vertex_position,1);" "\n"
 		"}" "\n"
 	;
 	const char * program_fragment_source =
@@ -35,7 +36,7 @@ main() {
 		"}" "\n"
 	;
 	GLuint program_ID = ogl_program_build(program_vertex_source, program_fragment_source);
-	GLint program_attribute_position_ID = glGetAttribLocation(program_ID, "attribute_position");
+	GLint program_va_vertex_position_ID = glGetAttribLocation(program_ID, "va_vertex_position");
 
 	const GLfloat triangle_vertexbuffer_data[] = { 
 		-1.0f, -1.0f, 0.0f,   1.0f, -1.0f, 0.0f,   0.0f,  1.0f, 0.0f,
@@ -49,12 +50,12 @@ main() {
 
 		glUseProgram(program_ID);
 
-		glEnableVertexAttribArray(program_attribute_position_ID);
+		glEnableVertexAttribArray(program_va_vertex_position_ID);
 		glBindBuffer(GL_ARRAY_BUFFER, triangle_vertexbuffer_ID);
-		glVertexAttribPointer(program_attribute_position_ID, 3, GL_FLOAT, GL_FALSE, 0, (GLvoid *)0);
+		glVertexAttribPointer(program_va_vertex_position_ID, 3, GL_FLOAT, GL_FALSE, 0, (GLvoid *)0);
 		glDrawArrays(GL_TRIANGLES, 0, triangle_vertexbuffer_data_vertexes);
 		glBindBuffer(GL_ARRAY_BUFFER, 0);
-		glDisableVertexAttribArray(program_attribute_position_ID);
+		glDisableVertexAttribArray(program_va_vertex_position_ID);
 
 		glfwSwapBuffers(window);
 		glfwPollEvents();