GLdc/GL/immediate.c
2021-10-01 21:02:13 +01:00

301 lines
8.2 KiB
C

/*
* This implements immediate mode over the top of glDrawArrays
* current problems:
*
* 1. Calling glNormal(); glVertex(); glVertex(); glVertex(); will break.
* 2. Mixing with glXPointer stuff will break badly
* 3. This is entirely untested.
*/
#include <string.h>
#include <stdio.h>
#include "private.h"
extern inline GLuint _glRecalcFastPath();
GLboolean IMMEDIATE_MODE_ACTIVE = GL_FALSE;
static GLenum ACTIVE_POLYGON_MODE = GL_TRIANGLES;
static GLfloat NORMAL[3] = {0.0f, 0.0f, 1.0f};
static GLubyte COLOR[4] = {255, 255, 255, 255}; /* ARGB order for speed */
static GLfloat UV_COORD[2] = {0.0f, 0.0f};
static GLfloat ST_COORD[2] = {0.0f, 0.0f};
static AlignedVector VERTICES;
static AttribPointerList IM_ATTRIBS;
/* We store the list of attributes that have been "enabled" by a call to
glColor, glNormal, glTexCoord etc. otherwise we already have defaults that
can be applied faster */
static GLuint IM_ENABLED_VERTEX_ATTRIBUTES = 0;
typedef struct {
GLfloat x;
GLfloat y;
GLfloat z;
GLfloat u;
GLfloat v;
GLfloat s;
GLfloat t;
GLubyte bgra[4];
GLfloat nx;
GLfloat ny;
GLfloat nz;
GLuint padding[5];
} IMVertex;
void _glInitImmediateMode(GLuint initial_size) {
aligned_vector_init(&VERTICES, sizeof(IMVertex));
aligned_vector_reserve(&VERTICES, initial_size);
IM_ATTRIBS.vertex.ptr = VERTICES.data;
IM_ATTRIBS.vertex.size = 3;
IM_ATTRIBS.vertex.type = GL_FLOAT;
IM_ATTRIBS.vertex.stride = sizeof(IMVertex);
IM_ATTRIBS.uv.ptr = IM_ATTRIBS.vertex.ptr + (sizeof(GLfloat) * 3);
IM_ATTRIBS.uv.stride = sizeof(IMVertex);
IM_ATTRIBS.uv.type = GL_FLOAT;
IM_ATTRIBS.uv.size = 2;
IM_ATTRIBS.st.ptr = IM_ATTRIBS.vertex.ptr + (sizeof(GLfloat) * 5);
IM_ATTRIBS.st.stride = sizeof(IMVertex);
IM_ATTRIBS.st.type = GL_FLOAT;
IM_ATTRIBS.st.size = 2;
IM_ATTRIBS.colour.ptr = IM_ATTRIBS.vertex.ptr + (sizeof(GLfloat) * 7);
IM_ATTRIBS.colour.size = GL_BGRA; /* Flipped color order */
IM_ATTRIBS.colour.type = GL_UNSIGNED_BYTE;
IM_ATTRIBS.colour.stride = sizeof(IMVertex);
IM_ATTRIBS.normal.ptr = IM_ATTRIBS.vertex.ptr + (sizeof(GLfloat) * 7) + sizeof(uint32_t);
IM_ATTRIBS.normal.stride = sizeof(IMVertex);
IM_ATTRIBS.normal.type = GL_FLOAT;
IM_ATTRIBS.normal.size = 3;
}
void APIENTRY glBegin(GLenum mode) {
if(IMMEDIATE_MODE_ACTIVE) {
_glKosThrowError(GL_INVALID_OPERATION, __func__);
return;
}
IMMEDIATE_MODE_ACTIVE = GL_TRUE;
ACTIVE_POLYGON_MODE = mode;
}
void APIENTRY glColor4f(GLfloat r, GLfloat g, GLfloat b, GLfloat a) {
IM_ENABLED_VERTEX_ATTRIBUTES |= DIFFUSE_ENABLED_FLAG;
COLOR[A8IDX] = (GLubyte)(a * 255.0f);
COLOR[R8IDX] = (GLubyte)(r * 255.0f);
COLOR[G8IDX] = (GLubyte)(g * 255.0f);
COLOR[B8IDX] = (GLubyte)(b * 255.0f);
}
void APIENTRY glColor4ub(GLubyte r, GLubyte g, GLubyte b, GLubyte a) {
IM_ENABLED_VERTEX_ATTRIBUTES |= DIFFUSE_ENABLED_FLAG;
COLOR[A8IDX] = a;
COLOR[R8IDX] = r;
COLOR[G8IDX] = g;
COLOR[B8IDX] = b;
}
void APIENTRY glColor4fv(const GLfloat* v) {
IM_ENABLED_VERTEX_ATTRIBUTES |= DIFFUSE_ENABLED_FLAG;
COLOR[B8IDX] = (GLubyte)(v[2] * 255);
COLOR[G8IDX] = (GLubyte)(v[1] * 255);
COLOR[R8IDX] = (GLubyte)(v[0] * 255);
COLOR[A8IDX] = (GLubyte)(v[3] * 255);
}
void APIENTRY glColor3f(GLfloat r, GLfloat g, GLfloat b) {
IM_ENABLED_VERTEX_ATTRIBUTES |= DIFFUSE_ENABLED_FLAG;
COLOR[B8IDX] = (GLubyte)(b * 255.0f);
COLOR[G8IDX] = (GLubyte)(g * 255.0f);
COLOR[R8IDX] = (GLubyte)(r * 255.0f);
COLOR[A8IDX] = 255;
}
void APIENTRY glColor3ub(GLubyte red, GLubyte green, GLubyte blue) {
IM_ENABLED_VERTEX_ATTRIBUTES |= DIFFUSE_ENABLED_FLAG;
COLOR[A8IDX] = 255;
COLOR[R8IDX] = red;
COLOR[G8IDX] = green;
COLOR[B8IDX] = blue;
}
void APIENTRY glColor3ubv(const GLubyte *v) {
IM_ENABLED_VERTEX_ATTRIBUTES |= DIFFUSE_ENABLED_FLAG;
COLOR[A8IDX] = 255;
COLOR[R8IDX] = v[0];
COLOR[G8IDX] = v[1];
COLOR[B8IDX] = v[2];
}
void APIENTRY glColor3fv(const GLfloat* v) {
IM_ENABLED_VERTEX_ATTRIBUTES |= DIFFUSE_ENABLED_FLAG;
COLOR[A8IDX] = 255;
COLOR[R8IDX] = (GLubyte)(v[0] * 255);
COLOR[G8IDX] = (GLubyte)(v[1] * 255);
COLOR[B8IDX] = (GLubyte)(v[2] * 255);
}
void APIENTRY glVertex3f(GLfloat x, GLfloat y, GLfloat z) {
IM_ENABLED_VERTEX_ATTRIBUTES |= VERTEX_ENABLED_FLAG;
unsigned int cap = VERTICES.capacity;
IMVertex* vert = aligned_vector_extend(&VERTICES, 1);
if(cap != VERTICES.capacity) {
/* Resizing could've invalidated the pointers */
IM_ATTRIBS.vertex.ptr = VERTICES.data;
IM_ATTRIBS.uv.ptr = IM_ATTRIBS.vertex.ptr + (sizeof(GLfloat) * 3);
IM_ATTRIBS.st.ptr = IM_ATTRIBS.vertex.ptr + (sizeof(GLfloat) * 5);
IM_ATTRIBS.colour.ptr = IM_ATTRIBS.vertex.ptr + (sizeof(GLfloat) * 7);
IM_ATTRIBS.normal.ptr = IM_ATTRIBS.vertex.ptr + (sizeof(GLfloat) * 7) + sizeof(uint32_t);
}
vert->x = x;
vert->y = y;
vert->z = z;
vert->u = UV_COORD[0];
vert->v = UV_COORD[1];
vert->s = ST_COORD[0];
vert->t = ST_COORD[1];
*((uint32_t*) vert->bgra) = *((uint32_t*) COLOR);
vert->nx = NORMAL[0];
vert->ny = NORMAL[1];
vert->nz = NORMAL[2];
}
void APIENTRY glVertex3fv(const GLfloat* v) {
glVertex3f(v[0], v[1], v[2]);
}
void APIENTRY glVertex2f(GLfloat x, GLfloat y) {
glVertex3f(x, y, 0.0f);
}
void APIENTRY glVertex2fv(const GLfloat* v) {
glVertex2f(v[0], v[1]);
}
void APIENTRY glVertex4f(GLfloat x, GLfloat y, GLfloat z, GLfloat w) {
_GL_UNUSED(w);
glVertex3f(x, y, z);
}
void APIENTRY glVertex4fv(const GLfloat* v) {
glVertex4f(v[0], v[1], v[2], v[3]);
}
void APIENTRY glMultiTexCoord2fARB(GLenum target, GLfloat s, GLfloat t) {
if(target == GL_TEXTURE0) {
IM_ENABLED_VERTEX_ATTRIBUTES |= UV_ENABLED_FLAG;
UV_COORD[0] = s;
UV_COORD[1] = t;
} else if(target == GL_TEXTURE1) {
IM_ENABLED_VERTEX_ATTRIBUTES |= ST_ENABLED_FLAG;
ST_COORD[0] = s;
ST_COORD[1] = t;
} else {
_glKosThrowError(GL_INVALID_ENUM, __func__);
return;
}
}
void APIENTRY glTexCoord2f(GLfloat u, GLfloat v) {
IM_ENABLED_VERTEX_ATTRIBUTES |= UV_ENABLED_FLAG;
UV_COORD[0] = u;
UV_COORD[1] = v;
}
void APIENTRY glTexCoord2fv(const GLfloat* v) {
glTexCoord2f(v[0], v[1]);
}
void APIENTRY glNormal3f(GLfloat x, GLfloat y, GLfloat z) {
IM_ENABLED_VERTEX_ATTRIBUTES |= NORMAL_ENABLED_FLAG;
NORMAL[0] = x;
NORMAL[1] = y;
NORMAL[2] = z;
}
void APIENTRY glNormal3fv(const GLfloat* v) {
glNormal3f(v[0], v[1], v[2]);
}
void APIENTRY glEnd() {
IMMEDIATE_MODE_ACTIVE = GL_FALSE;
GLuint* attrs = &ENABLED_VERTEX_ATTRIBUTES;
/* Redirect attrib pointers */
AttribPointerList stashed_attrib_pointers = ATTRIB_POINTERS;
ATTRIB_POINTERS = IM_ATTRIBS;
GLuint prevAttrs = *attrs;
*attrs = IM_ENABLED_VERTEX_ATTRIBUTES;
/* Store the fast path enabled setting so we can restore it
* after drawing */
const GLboolean fp_was_enabled = FAST_PATH_ENABLED;
#ifndef NDEBUG
// Immediate mode should always activate the fast path
GLuint fastPathEnabled = _glRecalcFastPath();
assert(fastPathEnabled);
#else
/* If we're not debugging, set to true - we assume we haven't broken it! */
FAST_PATH_ENABLED = GL_TRUE;
#endif
glDrawArrays(ACTIVE_POLYGON_MODE, 0, VERTICES.size);
ATTRIB_POINTERS = stashed_attrib_pointers;
*attrs = prevAttrs;
aligned_vector_clear(&VERTICES);
FAST_PATH_ENABLED = fp_was_enabled;
}
void APIENTRY glRectf(GLfloat x1, GLfloat y1, GLfloat x2, GLfloat y2) {
glBegin(GL_QUADS);
glVertex2f(x1, y1);
glVertex2f(x2, y1);
glVertex2f(x2, y2);
glVertex2f(x1, y2);
glEnd();
}
void APIENTRY glRectfv(const GLfloat *v1, const GLfloat *v2) {
glBegin(GL_QUADS);
glVertex2f(v1[0], v1[1]);
glVertex2f(v2[0], v1[1]);
glVertex2f(v2[0], v2[1]);
glVertex2f(v1[0], v2[1]);
glEnd();
}
void APIENTRY glRecti(GLint x1, GLint y1, GLint x2, GLint y2) {
return glRectf((GLfloat)x1, (GLfloat)y1, (GLfloat)x2, (GLfloat)y2);
}
void APIENTRY glRectiv(const GLint *v1, const GLint *v2) {
return glRectfv((const GLfloat *)v1, (const GLfloat *)v2);
}