Window, Surface and Stuffs

[KSP0O]

Split DRAW_POST out of the main draw flow to fix Undertale border/surface rendering issues and align behavior with the decompiled yoyo runner.

Implement proper glfw window dimension handling (window_get_width/height + window_set_size).

Implement application_surface_enable and application_surface_draw_enable builtins to control application surface usage and auto-draw behavior.

[Fancy2209]

Could you resolve conflicts and rebase on main?

[KSP0O]

Could you resolve conflicts and rebase on main?

Done, I think everything is set now.

[MrPowerGamerBR]

The Post-Draw order is incorrect

The Pre-Draw and Post-Draw events are part of the Draw Event category. However, unlike the other Draw events these draw directly to the display buffer, which will be the size of the combined screen space for all viewports currently visible, or the window size if only using one viewport or none at all.

The Post-Draw must be, conceptually, here

void GLCommon_letterboxBlit(GLuint fbo, int32_t fboWidth, int32_t fboHeight, int32_t gameW, int32_t gameH, int32_t windowW, int32_t windowH) {
    int32_t sx, sy, ex, ey;
    GLCommon_computeLetterbox(gameW, gameH, windowW, windowH, &sx, &sy, &ex, &ey);
    glBindFramebuffer(GL_READ_FRAMEBUFFER, fbo);
    glBindFramebuffer(GL_DRAW_FRAMEBUFFER, 0);
    // Post Draw
    glBlitFramebuffer(0, 0, fboWidth, fboHeight, sx, sy, ex, ey, GL_COLOR_BUFFER_BIT, GL_NEAREST);
    glBindFramebuffer(GL_FRAMEBUFFER, 0);
}

For that it will require changing the vtable to split up both parts of the GLCommon_letterboxBlit (which is called on endFrame)

[MrPowerGamerBR]

For reference, here's how GameMaker-HTML5 does it

	this.PreDraw(r);
	//this.SetApplicationSurface();				
	this.DrawViews(r);	
	// Disable application_surface, and now render direct to the screen
	if (g_bUsingAppSurface) {
	    surface_reset_target();
	}
	//check surface stack is empty
	if (g_SurfaceStack.length != 0)
	{
	    yyError("Unbalanced surface stack. You MUST use surface_reset_target() for each set.");
	    return;
	}		
	this.PostDraw(r);
    this.DrawApplicationSurface(r);
	this.DrawGUI(r);
	this.DrawCursor(r);
	Graphics_Restore();
};

As a reference, here's the GLFW target

        Runner_drawViews(runner, gameW, gameH, displayScaleX, displayScaleY, debugShowCollisionMasks); // GM-HTML5 drawViews

        renderer->vtable->endFrame(renderer); // Bind Framebuffer + Draw Application Surface

...and while writing this (unrelated to this PR), I think the Draw GUI event is also out of order, it should be done after Post-Draw, after the application surface has been drawn, currently it is drawn on Runner_drawViews